Thermosetting composition with photo-alignment property, alignment layer, substrate with alignment layer, retardation plate, and device

ABSTRACT

An embodiment of the present invention provides a thermosetting composition with a photo-alignment property, including a copolymer containing a photo-alignment constitutional unit represented by the following formula (1) and a thermal cross-linking constitutional unit. In the formula (1), X represents a photo-alignment group causing a photo-isomerization reaction or a photo-dimerization reaction, L 1  represents a single bond, —O—, —S—, —COO—, —COS—, —CO—, —OCO—, —OCO(CH 2 ) n COO—, —OCOCH 2 CH 2 OCH 2 CH 2 COO—, —OCOC 6 H 4 O—, —OCOC 6 H 10 O—, —COO(CH 2 ) n O—, —COOC 6 H 4 O—, —COOC 6 H 10 O—, —O(CH 2 ) n O—, —OC 6 H 4 O—, —OC 6 H 10 O—, or —(CH 2 ) n O—, n represents 1 to 4, R 1  represents a hydrogen atom or a monovalent organic group, and k represents 1 to 5.

TECHNICAL FIELD

The present invention relates to a thermosetting composition with aphoto-alignment property, which is used for an alignment layer.

BACKGROUND ART

With regard to a liquid crystal, diverse applications to various kindsof optical elements such as a retardation plate and a polarizing plateexcept a liquid crystal display element have been studied by utilizingan alignment property and anisotropy of physical properties such asrefractive index, dielectric constant and magnetic susceptibility.

An alignment layer is used for aligning a liquid crystal. A rubbingmethod and a photo-alignment method are known as examples of a formationmethod for an alignment layer, and the photo-alignment method is usefulin view of being capable of controlling quantitative alignment treatmentby reason of no occurrence of static electricity and dust as a problemof the rubbing method (refer to Patent Document 1, for example).

Thermal stability and solvent resistance except liquid crystal alignmentability are required for an alignment layer. For example, the alignmentlayer is occasionally exposed to heat and solvents in the productionprocess of various kinds of devices, and to high temperature during theuse of various kinds of devices. The exposure of the alignment layer tohigh temperature brings a possibility of remarkably deteriorating liquidcrystal alignment ability.

Then, for example, in Patent Document 2, in order to obtain stableliquid crystal alignment ability, a liquid crystal alignment agentcontaining a polymer component having a structure capable of across-inking reaction by light and a structure which cross-links byheat, and a liquid crystal alignment agent containing a polymercomponent having a structure capable of a cross-inking reaction by lightand a compound having a structure which cross-links by heat areproposed.

Also, in Patent Document 3, in order to obtain excellent liquid crystalalignment ability, sufficient thermal stability, high solvent resistanceand high transparency, a thermosetting film forming composition having aphoto-alignment property, containing (A) an acrylic copolymer having aphoto-dimerization site and a thermal cross-linking site and (B) across-linking agent, is proposed. (B) The cross-linking agent bonds to athermal cross-linking site of (A) the acrylic copolymer, and thethermosetting film forming composition having a photo-alignment propertyis cured by heating to form a cured film, and then an alignment layermay be formed by irradiating the cured film with polarized ultravioletrays.

In Patent Document 4, in order to obtain excellent liquid crystalalignment ability, sufficient thermal stability, high solvent resistanceand high transparency, a thermosetting film forming composition having aphoto-alignment property, containing (A) an acrylic copolymer having aphoto-dimerization site and a thermal cross-linking site, (B) an acrylicpolymer having at least one of predetermined alkyl ester group andhydroxyalkyl ester group, and at least one of a carboxyl group and aphenolic hydroxy group, and (C) a cross-linking agent, is proposed. (C)The cross-linking agent bonds to a thermal cross-linking site of (A) theacrylic copolymer and to a carboxyl group and a phenolic hydroxy groupof (B) the acrylic polymer, and the thermosetting film formingcomposition having a photo-alignment property is cured by heating toform a cured film, and then an alignment layer may be formed byirradiating the cured film with polarized ultraviolet rays.

In Patent Document 5, in order to obtain excellent liquid crystalalignment ability, sufficient thermal stability, high solvent resistanceand high transparency, a thermosetting film forming composition having aphoto-alignment property, containing (A) a compound having aphoto-alignment group and a hydroxy group, (B) a polymer having at leastone of a hydroxy group and a carboxyl group, and (C) a cross-linkingagent, is proposed. (C) The cross-linking agent bonds to a hydroxy groupof (A) the compound and to a hydroxy group and a carboxyl group of (B)the polymer, and the thermosetting film forming composition having aphoto-alignment property is cured by heating to form a cured film, andthen an alignment layer may be formed by irradiating the cured film withpolarized ultraviolet rays.

CITATION LIST Patent Documents

-   Patent Document 1: Japanese Patent (JP-B) No. 4094764-   Patent Document 2: JP-B 4207430-   Patent Document 3: WO 2010/150748-   Patent Document 4: WO 2011/010635-   Patent Document 5: WO 2011/126022-   Patent Document 6: WO 2014/104320

SUMMARY

In these manners, thermal curing is proposed for improving thermalstability and solvent resistance of an alignment layer. However, thermalcuring may cause decrease in photoreactivity in some cases. Inparticular, as Patent Documents 3 and 4, when the acrylic copolymerincludes both a photo-dimerization site and a thermal cross-linkingsite, it is considered that the dimerization is hardly caused since thephoto-dimerization sites of side chains of the acrylic copolymer in thecured film are separated from each other.

The irradiation dose of polarized ultraviolet rays may be increased andthe irradiation time may be increased for improving alignmentrestraining force, but throughput decreases in that case. Accordingly,improvement of the sensitivity of the material to be used for thealignment layer to light is demanded to decrease the irradiation dose ofpolarized ultraviolet rays and to decrease the irradiation time alsofrom the view point of energy saving.

The present disclosure has been made in view of the problem, and anobjective thereof is to provide a thermosetting composition with a highsensitive photo-alignment property in the thermosetting compositioncontaining a copolymer including both a photo-alignment site and athermal cross-linking site, and provide an alignment layer, a substratewith the alignment layer, a retardation plate and a device using thethermosetting composition.

An embodiment of the present invention provides a thermosettingcomposition having a photo-alignment property, comprising a copolymercontaining a photo-alignment constitutional unit represented by thefollowing formula (1) and a thermal cross-linking constitutional unit:

(in the formula (1), X represents a photo-alignment group causing aphoto-isomerization reaction or a photo-dimerization reaction, L¹represents a single bond, —O—, —S—, —COO—, —COS—, —CO—, —OCO—,—OCO(CH₂)_(n)COO—, —OCOCH₂CH₂OCH₂CH₂COO—, —OCOC₆H₄O—, —OCOC₆H₁₀O—,—COO(CH₂)_(n)O—, —COOC₆H₄O—, —COOC₆H₁₀O—, —O(CH₂)_(n)O—, —OC₆H₄O—,—OC₆H₁₀O—, or —(CH₂)_(n)O—, n represents 1 to 4, R¹ represents ahydrogen atom or a monovalent organic group, and k represents 1 to 5).

Further, an embodiment of the present invention provides an alignmentlayer comprising a copolymer including a photo-alignment constitutionalunit represented by the formula (1) and a cross-linking structure, andthe alignment layer comprising a photo-dimerization structure or aphoto-isomerization structure of a photo-alignment group in thephoto-alignment constitutional unit.

Also, an embodiment of the present invention provides a substrate withan alignment layer comprising a substrate, and an alignment layerdisposed on the substrate and formed from the thermosetting compositionwith a photo-alignment property or the alignment layer described above.

Also, an embodiment of the present invention provides a retardationplate comprising the substrate with an alignment layer described aboveand a retardation layer disposed on the alignment layer of the substratewith the alignment layer.

In addition, an embodiment of the present invention provides a devicecomprising an alignment layer formed from the thermosetting compositionwith a photo-alignment property or the alignment layer described above.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic sectional view showing an example of a substratewith an alignment layer of an embodiment of the present invention.

FIG. 2 is a schematic sectional view showing an example of a retardationplate in an embodiment of the present invention.

FIG. 3 is a schematic sectional view showing an example of a liquidcrystal display element in an embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

A thermosetting composition with a photo-alignment property, and analignment layer, a substrate with the alignment layer, a retardationplate and a device using the thermosetting composition of an embodimentof the present invention are hereinafter described in detail.

A. Thermosetting Composition with Photo-Alignment Property

A thermosetting composition with a photo-alignment property of anembodiment of the present invention comprises a copolymer containing aphoto-alignment constitutional unit represented by the following formula(1) and a thermal cross-linking constitutional unit.

(In the formula (1), X represents a photo-alignment group causing aphoto-isomerization reaction or a photo-dimerization reaction, L¹represents a single bond, —O—, —S—, —COO—, —COS—, —CO—, —OCO—,—OCO(CH₂)_(n)COO—, —OCOCH₂CH₂OCH₂CH₂COO—, —OCOC₆H₄O—, —OCOC₆H₁₀O—,—COO(CH₂)_(n)O—, —COOC₆H₄O—, —COOC₆H₁₀O—, —O(CH₂)_(n)O—, —OC₆H₄O—,—OC₆H₁₀O—, or —(CH₂)_(n)O—, n represents 1 to 4, R¹ represents ahydrogen atom or a monovalent organic group, and k represents 1 to 5.)

In an embodiment of the present invention, the copolymer contains thephoto-alignment constitutional unit represented by the formula (1) sothat photo-dimerization reactivity or photo-isomerization reactivity maybe enhanced to improve sensitivity. The reason therefor is not clear,but surmised as follows. That is to say, the photo-alignmentconstitutional unit includes a styrene skeleton so that a stackingstructure is easily formed by an interaction of the n-electron systemsof styrene skeletons of the photo-alignment constitutional unit. Also,in the photo-alignment constitutional unit represented by the formula(1), L¹ is a single bond or a divalent linking group with short chainlength, and the photo-alignment group and the styrene skeleton areclose. Thus, it is surmised that the photo-alignment group is in thepositional relationship of easily causing a photo-isomerization reactionor a photo-dimerization reaction. For example, in the case of aphoto-isomerization reaction, it is conceived that styrene skeletons ofthe photo-alignment constitutional unit are stacked and thephoto-alignment group and the styrene skeleton are so close that thephoto-alignment group is easily aligned to improve photo-isomerizationreactivity. Also, in the case of a photo-dimerization reaction, it isconceived that styrene skeletons of the photo-alignment constitutionalunit are stacked and the photo-alignment group and the styrene skeletonare so close that the distance between the photo-alignment groups isshortened to improve photo-dimerization reactivity.

Accordingly, in an embodiment of the present invention, a thermosettingcomposition with a high-sensitive photo-alignment property, capable offorming an alignment layer at small light exposure, may be obtained.Consequently, an embodiment of the present invention is useful inviewpoint of energy saving since their radiation dose of polarizedultraviolet rays during the formation of the alignment layer may bedecreased to shorten the irradiation time.

Also, in an embodiment of the present invention, the copolymer containsthe photo-alignment constitutional unit represented by the formula (1)so that an alignment layer with favorable liquid crystal alignmentability may be obtained. The reason therefor is not clear but surmisedas follows. That is to say, the photo-alignment constitutional unitrepresented by the formula (1) includes a styrene skeleton and containsmany n-electron systems. Also, generally, many liquid crystal moleculeshave an aromatic ring such as a benzene ring and contain n-electronsystems similarly. In addition, in the photo-alignment constitutionalunit represented by the formula (1), L¹ is a single bond or a divalentlinking group with short chain length, and the photo-alignment group andthe styrene skeleton are so close that the structure becomes similar toa structure of a liquid crystal molecule, compared with a divalentlinking group with comparatively long chain length. Thus, the alignmentlayer formed from the thermosetting composition with a photo-alignmentproperty of an embodiment of the present invention may be strong in theinteraction with the liquid crystal molecules. In these manners, it isconceived that the liquid crystal molecules may be easily controlled,and thus favorable liquid crystal alignment ability may be obtained.Also, in the liquid crystal alignment layer formed from thethermosetting composition with a photo-alignment property of anembodiment of the present invention, it is conceived that the adhesionproperties to a liquid crystal layer disposed on this liquid crystalalignment layer may also be improved by the interaction of n-electronsystems.

Also, the thermosetting composition with a photo-alignment property ofan embodiment of the present invention includes a thermosetting propertyto allow the alignment layer excellent in thermal stability and solventresistance to be obtained. Also, the thermosetting composition with aphoto-alignment property of an embodiment of the present invention ishighly sensitive so that the liquid crystal alignment ability may beobtained even in the case the content of the photo-alignmentconstitutional unit in the copolymer is comparatively small. Thus, thecontent of the thermosetting constitutional unit in the copolymer may berelatively increased and thus thermal stability and solvent resistantmay further be improved.

Further, the thermosetting composition is suitable for mass productionby reason of high sensitivity, and the productivity of a deviceincluding the alignment layer formed from the thermosetting compositionwith a photo-alignment property may be also improved.

Each component in the thermosetting composition with a photo-alignmentproperty of an embodiment of the present invention is hereinafterdescribed.

1. Copolymer

A copolymer used for an embodiment of the present invention contains thephoto-alignment constitutional unit represented by the formula (1) and athermal cross-linking constitutional unit.

Each constitutional unit in the copolymer is hereinafter described.

(1) Photo-Alignment Constitutional Unit

The photo-alignment constitutional unit in an embodiment of the presentinvention is represented by the following formula (1), and is a site fordeveloping anisotropy by causing a photo-isomerization reaction or aphoto-dimerization reaction due to light irradiation.

(In the formula (1), X represents a photo-alignment group causing aphoto-isomerization reaction or a photo-dimerization reaction, L¹represents a single bond, —O—, —S—, —COO—, —COS—, —CO—, —OCO—,—OCO(CH₂)_(n)COO—, —OCOCH₂CH₂OCH₂CH₂COO—, —OCOC₆H₄O—, —OCOC₆H₁₀O—,—COO(CH₂)_(n)O—, —COOC₆H₄O—, —COOC₆H₁₀O—, —O(CH₂)_(n)O—, —OC₆H₄O—,—OC₆H₁₀O—, or —(CH₂)_(n)O—, n represents 1 to 4, R¹ represents ahydrogen atom or a monovalent organic group, and k represents 1 to 5.)

X in the formula (1) is a photo-alignment group for causing aphoto-isomerization reaction or a photo-dimerization reaction.

Examples of the photo-alignment group which causes a photo-dimerizationreaction may include a cinnamoyl group, a chalcone group, a coumaringroup, an anthracene group, a quinoline group, an azobenzene group, anda stilbene group. A benzene ring in these functional groups may includea substituent. The substituent may be such as not to prevent aphoto-dimerization reaction, and examples thereof may include an alkylgroup, an aryl group, a cycloalkyl group, an alkoxy group, a hydroxygroup, a halogen atom, a trifluoromethyl group, and a cyano group.

The photo-alignment group which causes a photo-isomerization reaction ispreferably such as to cause a cis-trans isomerization reaction, andexamples thereof may include a cinnamoyl group, a chalcone group, anazobenzene group, and a stilbene group. Abenzene ring in thesefunctional groups may include a substituent. The substituent may be suchas not to prevent a photo-isomerization reaction, and examples thereofmay include an alkoxy group, an alkyl group, a halogen atom, atrifluoromethyl group, and a cyano group.

Above all, the photo-alignment group is preferably a cinnamoyl group.Specifically, the cinnamoyl group is preferably a group represented bythe following formulae (2-1) and (2-2).

In the formula (2-1), R¹¹ represents a hydrogen atom, an alkyl groupwith a carbon number of 1 to 18, an aryl group with a carbon number of 1to 18 or a cycloalkyl group with a carbon number of 1 to 18. However,the alkyl group, the aryl group and the cycloalkyl group may be bondedthrough an ether linkage, an ester linkage, an amide linkage, and a urealinkage, and may include a substituent. R¹² to R¹⁵ each independentlyrepresent a hydrogen atom, a halogen atom, an alkyl group with a carbonnumber of 1 to 18, an aryl group with a carbon number of 1 to 18 or acycloalkyl group with a carbon number of 1 to 18, an alkoxy group with acarbon number of 1 to 18 or a cyano group. However, the alkyl group, thearyl group and the cycloalkyl group may be bonded through an etherlinkage, an ester linkage, an amide linkage, and a urea linkage, and mayinclude a substituent. R¹⁶ and R¹⁷ each independently represent ahydrogen atom, a halogen atom, an alkyl group with a carbon number of 1to 18, an aryl group with a carbon number of 1 to 18 or an alkoxy groupwith a carbon number of 1 to 18.

Also, in the formula (2-2), R²¹ to R²⁵ each independently represent ahydrogen atom, a halogen atom, an alkyl group with a carbon number of 1to 18, an aryl group with a carbon number of 1 to 18 or a cycloalkylgroup with a carbon number of 1 to 18, an alkoxy group with a carbonnumber of 1 to 18 or a cyano group. However, the alkyl group, the arylgroup and the cycloalkyl group may be bonded through an ether linkage,an ester linkage, an amide linkage, and a urea linkage, and may includea substituent. R²⁶ and R²⁷ each independently represent a hydrogen atom,a halogen atom, an alkyl group with a carbon number of 1 to 18, an arylgroup with a carbon number of 1 to 18 or an alkoxy group with a carbonnumber of 1 to 18.

Incidentally, in the case the photo-alignment group is a cinnamoylgroup, which is represented by the formula (2-1), a benzene ring of astyrene skeleton may be a benzene ring of the cinnamoyl group.

L in the formula (1) is a single bond, —O—, —S—, —COO—, —COS—, —CO—,—OCO—, —OCO(CH₂)_(n)COO—, —OCOCH₂CH₂OCH₂CH₂COO—, —OCOC₆H₄O—,—OCOC₆H₁₀O—, —COO(CH₂)_(n)O—, —COOC₆H₄O—, —COOC₆H₁₀O—, —O(CH₂)_(n)O—,—OC₆H₄O—, —OC₆H₁₀O—, or —(CH₂)_(n)O—, and “n” is 1 to 4. Incidentally,in the case L¹ is a single bond, the photo-alignment group X is directlybonded to a styrene skeleton.

Above all, L is preferably a single bond, —O—, —S—, —COO—, —COS—, —CO—,or —OCO—. L¹ is a single bond or the chain length of the divalentlinking group is further shortened so that the photo-alignment group andthe styrene skeleton may be further closer in the photo-alignmentconstitutional unit. Thus, it is surmised that the photo-alignment groupis in the positional relationship of easily causing aphoto-isomerization reaction or a photo-dimerization reaction. Forexample, in the case of a photo-isomerization reaction, it is conceivedthat styrene skeletons of the photo-alignment constitutional unit arestacked and the photo-alignment group and the styrene skeleton are soclose that the photo-alignment group is easily aligned to furtherimprove photo-isomerization reactivity. Also, in the case of aphoto-dimerization reaction, it is conceived that styrene skeletons ofthe photo-alignment constitutional unit are stacked and thephoto-alignment group and the styrene skeleton are so close that thedistance between the photo-alignment groups is shortened to furtherimprove photo-dimerization reactivity. Accordingly, the sensitivity maybe further improved. Also, the photo-alignment group and the styreneskeleton are so close in the photo-alignment constitutional unit thatthe structure becomes further similar to a structure of a liquid crystalmolecule. Thus, it is conceived that an affinity with a liquid crystallayer disposed on the alignment layer becomes so high as to improveliquid crystal alignment ability and adhesion properties to the liquidcrystal layer.

R¹ in the formula (1) is a hydrogen atom or a monovalent organic group.The monovalent organic group is preferably a methyl group. Above all, R¹is preferably a hydrogen atom.

In the formula (1), “k” is 1 to 5, and -L¹-X may be bonded to any of anortho-position, a meta-position, and a para-position. In the case “k” is2 to 5, L¹ and X may be the same or different mutually. Above all, it ispreferable that “k” is 1, and -L¹-X is bonded to a para-position.Specifically, the photo-alignment constitutional unit is preferably aconstitutional unit represented by the following formula (1-1).Incidentally, in the following formula, each sign is the same as in theformula (1).

A constitutional unit represented by the following formulae (1-2) to(1-5) may be exemplified as the photo-alignment constitutional unit.

In the formula (1-2), R³¹ is the same as R¹¹ of the formula (2-1), andR³² and R³³ are the same as R¹⁶ and R¹⁷ of the formula (2-1).

In the formula (1-3), L¹¹ is the same as L¹ of the formula (1), and R¹¹to R¹⁷ are the same as in the formula (2-1).

In the formula (1-4), L¹² is the same as L¹ of the formula (1) exceptfor —COS— and —CO—.

In the formula (1-5), L¹³ is the same as L¹ of the formula (1). R³⁵ toR³⁷ are the same as R¹² to R¹⁵ of the formula (2-1), and R³⁸ and R³⁹ arethe same as R¹⁶ and R¹⁷ of the formula (2-1)

The photo-alignment constitutional unit of the copolymer may be onekind, or two kinds or more.

Above all, the photo-alignment constitutional unit is preferably aconstitutional unit represented by the formulae (1-3) and (1-4).

In the formula (1-3), L¹¹ is preferably —O—, —S—, —COO—, —COS—, —CO—, or—OCO— in view of sensitivity.

Also, the photo-alignment constitutional unit represented by the formula(1-3) is more preferably a constitutional unit represented by thefollowing formula (1-6).

In the formula (1-6), R¹² to R¹⁷ and L¹¹ are the same as in the formula(1-3). R¹⁸ represents a hydrogen atom, an alkoxy group with a carbonnumber of 1 to 18, a cyano group, an alkyl group with a carbon number of1 to 18, a phenyl group, a biphenyl group or a cyclohexyl group.However, the alkyl group, the phenyl group, the biphenyl group and thecyclohexyl group may be bonded through an ether linkage, an esterlinkage, an amide linkage, and a urea linkage. The value “j” represents1 to 5, and R¹⁸ may be bonded to any of an ortho-position, ameta-position, and a para-position. In the case “j” is 2 to 5, R¹⁸ maybe the same or different mutually. Above all, it is preferable that “j”is 1, and R¹⁸ is bonded to a para-position.

Also, in the formula (1-4), L¹² is preferably —O—, —S—, —COO—, or —OCO—in view of sensitivity.

In the case the photo-alignment constitutional unit is a constitutionalunit represented by the formulae (1-6) and (1-4), an aromatic ring isdisposed in the vicinity of the end of the photo-alignmentconstitutional unit to contain many r-electrons. Thus, an affinity for aliquid crystal layer disposed on the alignment layer is conceived tobecome so higher as to improve adhesion properties to the liquid crystallayer.

Also, in this case, it is conceived that the photo dimerization reactionis easily caused. A double bond of a cinnamoyl group for causing thephoto-dimerization reaction is so close to the styrene skeleton thatstyrene skeletons in the photo-alignment constitutional unit arestacked, and thus the distance between the double bonds of the cinnamoylgroup for causing the photo-dimerization reaction may be furthershortened. Thus the photo-dimerization reactivity may be furtherincreased and sensitivity may be further improved.

A styrene-based monomer including the photo-alignment group for formingthe photo-alignment constitutional unit may be used for synthesizing thecopolymer. The styrene-based monomer including the photo-alignment groupmay be used singly or in combination of two kinds or more.

The content of the photo-alignment constitutional unit in the copolymermay be determined within a range of about 10% by mol to 90% by mol,preferably within a range of about 20% by mol to 80% by mol when thewhole copolymer is regarded as 100% by mol. The low content of thephoto-alignment constitutional unit occasionally deterioratessensitivity to allow favorable liquid crystal alignment ability withdifficulty. Also, the high content of the photo-alignment constitutionalunit occasionally decreases the content of the thermal cross-linkingconstitutional unit relatively to maintain favorable liquid crystalalignment ability with difficulty by reason of not obtaining asufficient thermosetting property.

Incidentally, the content of each constitutional unit in the copolymermay be calculated from an integral value by ¹H NMR measurement.

(2) Thermal Cross-Linking Constitutional Unit

The thermal cross-linking constitutional unit in an embodiment of thepresent invention is a site for bonding to a cross-linking agent byheating.

The thermal cross-linking constitutional unit includes a thermalcross-linking group. Examples of the thermal cross-linking group mayinclude a hydroxy group, a carboxy group, a phenolic hydroxy group, amercapto group, a glycidyl group, and an amide group. Above all, fromthe viewpoint of reactivity, an aliphatic hydroxy group is preferable,and a primary hydroxy group is more preferable.

Examples of a monomer unit constituting the thermal cross-linkingconstitutional unit may include acrylate, methacrylate, styrene,acrylamide, methacrylamide, maleimide, vinyl ether, and vinyl ester.Above all, acrylate, methacrylate, and styrene are preferable. Also, asdescribed later, in the case the thermal cross-linking constitutionalunit includes a self-cross-linkable cross-linking group, acrylate,methacrylate, acrylamide, methacrylamide, and styrene are preferable.

The monomer of acrylate and methacrylate has the advantages thatsolubility is high, easily obtained as a commercial product, andreactivity during copolymerization is favorable.

Also, in the case of styrene, in the copolymer, not only thephoto-alignment constitutional unit but also the thermal cross-linkingconstitutional unit includes a styrene skeleton so as to allow thecopolymer to contain many r-electron systems. Thus, in the case offorming an alignment layer by using the thermosetting composition with aphoto-alignment property of an embodiment of the present invention, aninteraction of the n-electron systems is conceived to allow liquidcrystal alignment ability and adhesion properties to a liquid crystallayer to be improved.

Also, the monomer of acrylamide and methacrylamide, to which theself-cross-linkable cross-linking group such as an N-alkoxymethyl groupand an N-hydroxymethyl group is bonded, has the advantages that easilyavailable as a commercial product and reactivity is favorable.

A constitutional unit represented by the following formula (3) may beexemplified as the thermal cross-linking constitutional unit.

In the formula (3), Z¹ represents a monomer unit and examples thereofmay include acrylate, methacrylate, acrylamide, methacrylamide, styrene,maleimide, vinyl ether and vinyl ester. Above all, as described above,acrylate, methacrylate, and styrene are preferable. Also, in the casethe thermal cross-linking constitutional unit includes aself-cross-linkable cross-linking group, as described above, acrylate,methacrylate, acrylamide, methacrylamide, and styrene are preferable.Specific examples thereof may include a monomer unit represented by thefollowing formula.

(In the formula, R⁴¹ represents a hydrogen atom, a methyl group, achlorine atom or a phenyl group, R⁴² represents a hydrogen atom or amethyl group, R⁴³ represents a hydrogen atom, a methyl group, a chlorineatom or a phenyl group, and R⁴⁴ represents a hydrogen atom or a loweralkyl group.)

In the case the monomer unit is styrene, -L²-Y may be bonded to any ofan ortho-position, a meta-position, and a para-position, or a pluralitythereof. In the case of a plurality, L² and Y may be the same ordifferent mutually. Above all, it is preferable that -L²-Y is one andbonded to a para-position.

In the formula (3), Y represents the thermal cross-linking group, andexamples thereof may include a hydroxy group, a carboxy group, aphenolic hydroxy group, a mercapto group, a glycidyl group, and an amidegroup. Above all, as described above, from the viewpoint of reactivity,an aliphatic hydroxy group is preferable, and a primary hydroxy group ismore preferable. Also, in the case the thermal cross-linkingconstitutional unit includes a self-cross-linkable cross-linking groupas the thermal cross-linking group, Y represents the self-cross-linkablecross linking group; as described later, examples thereof may include aphenolic hydroxy group of which ortho-position is substituted with ahydroxymethyl group or an alkoxymethyl group, a glycidyl group, an amidegroup, an N-alkoxymethyl group, and an N-hydroxymethyl group.

In the formula (3), L² represents a single bond or a divalent linkinggroup. Incidentally, in the case L² is the single bond, the thermalcross-linking group Y is directly bonded to the monomer unit Z².Examples of the divalent linking group may include an ether linkage, athioether linkage, an ester linkage, a thioester linkage, a carbonyllinkage, a thiocarbonyl linkage, an alkylene group, an arylene group, acycloalkylene group, and combinations of these. Above all, the divalentcross-linking group preferably include —(CH₂)_(n)— or —(C₂H₄O)_(m)—, “n”is preferably 4 to 11, and “m” is preferably 2 to 5. When “n” and “m”are too small, the distance between the thermal cross-linking group andthe main skeleton of the copolymer is shortened in the thermalcross-linking constitutional unit so that a cross-linking agent bonds tothe thermal cross-linking group with difficulty to bring a possibilityof deteriorating reactivity between the thermal cross-linkingconstitutional unit and the cross-linking agent. On the other hand, when“n” and “m” are too large, the chain length of the linking groupincreases in the thermal cross-linking constitutional unit so that thethermal cross-linking group at the end comes out on the surface withdifficulty and a cross-linking agent bonds to the thermal cross-linkinggroup with difficulty to bring a possibility of deteriorating reactivitybetween the thermal cross-linking constitutional unit and thecross-linking agent.

Incidentally, for example, in the case L² is —(C₂H₄O)_(m)—, and Y is ahydroxy group, -L²-Y may be —(C₂H₄O)_(m)—H.

Also, in the formula (3), the thermal cross-linking group Y is bonded tothe monomer unit Z¹ via a divalent cross-linking group or the singlebond L², but in the case Y is a carboxy group or a hydroxy group, thethermal cross-linking constitutional unit represented by the formula (3)may be the constitutional unit represented by the following formula.Incidentally, in the following formula, each sign is the same as in theabove formula.

Also, the thermal cross-linking constitutional unit may include across-linking group. In this case, the thermal cross-linkingconstitutional unit may also serve as a cross-linking agent. That is tosay, the cross-linking group is a self-cross-linkable group. Also, thethermal cross-linking constitutional unit includes the cross-linkinggroup as the thermal cross-linking group.

Here, self-cross-linking signifies that the same functional groups ordifferent functional groups react without the cross-linking agent toform a cross-linking structure.

In the case of using the copolymer including such a thermalcross-linking constitutional unit, the thermosetting composition with aphoto-alignment property of an embodiment of the present invention maybe utilized without adding the cross-linking agent. Thus, the content ofthe copolymer in the thermosetting composition with a photo-alignmentproperty may be increased relatively and the content of thephoto-alignment constitutional unit for contributing to the alignmentmay be increased relatively to improve photoreactivity. Also, generally,the cross-linking agent is a low-molecular component, and no addition ofthe cross-linking agent may prevent the cross-linking agent from comingup to the surface of the alignment layer, that is, bleedout, and mayinhibit liquid crystal alignment ability from being hindered.Accordingly, photoreactivity and sensitivity may be further improved.

Meanwhile, it is preferable that the thermal cross-linkingconstitutional unit does not include a cross-linking group in view ofstorage stability.

Examples of the thermal cross-linking constitutional unit including thecross-linking group may include one including a phenolic hydroxy groupof which ortho-position is substituted with a hydroxymethyl group or analkoxymethyl group, a glycidyl group, an amide group, an N-alkoxymethylgroup, and an N-hydroxymethyl group.

Examples of a monomer for forming such a thermal cross-linkingconstitutional unit may include an acrylate compound, a methacrylatecompound, an acrylamide compound, a methacrylamide compound, a styrenecompound, a maleimide compound, and a vinyl compound.

Examples of the acrylate compound and the methacrylate compound mayinclude a monomer including a hydroxy group and an acryl group or amethacryl group such as 2-hydroxyethyl acrylate, 2-hydroxyethylmethacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate,4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate,2,3-dihydroxypropyl acrylate, 2,3-dihydroxypropyl methacrylate,diethylene glycol monoacrylate, diethylene glycol monomethacrylate,triethylene glycol monoacrylate, tetraethylene glycol monoacrylate,dipropylene glycol monoacrylate, tripropylene glycol monoacrylate, andtetrapropylene glycol monoacrylate.

Examples of the acrylamide compound and the methacrylamide compound mayinclude a monomer including a hydroxy group and an acrylamide group or amethacrylamide group such as 2-hydroxyethyl acrylamide, 2-hydroxyethylmethacrylamide, 2-hydroxypropyl acrylamide, 2-hydroxypropylmethacrylamide, 4-hydroxybutyl acrylamide, and 4-hydroxybutylmethacrylamide.

Examples of the vinyl compound may include a monomer including a hydroxygroup and a vinyl group such as 2-hydroxyethyl vinyl ether,3-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, diethyleneglycol monovinyl ether, and 3-hydroxy vinylpropionate.

Examples of the styrene compound may include a monomer including ahydroxy group and a styrene group such as an ester compound of 4-vinylbenzoate and diol, an ester compound of 4-vinyl benzoate and diethyleneglycol, an ether compound of hydroxystyrene and diol, and an ethercompound of hydroxystyrene and diethylene glycol.

Examples of the maleimide compound may include a monomer including ahydroxy group and a maleimide group such as N-(2-hydroxyethyl)maleimideand N-hydroxy maleimide.

Also, a monomer including a phenolic hydroxyl group such ashydroxystyrene, N-(hydroxyphenyl)methacrylamide, N-(hydroxyphenyl)acrylamide, and N-(hydroxyphenyl) maleimide, a monomer including acarboxy group such as acrylic acid, methacrylic acid, crotonic acid,mono-(2-(acryloyloxy)ethyl)phthalate,mono-(2-(metacryloyloxy)ethyl)phthalate, N-(carboxyphenyl)maleimide,N-(carboxyphenyl)methacrylamide, and N-(carboxyphenyl)acrylamide, andmonomers including a glycidyl group such as glycidyl methacrylate andglycidyl acrylate may be exemplified.

The thermal cross-linking constitutional unit of the copolymer may beone kind, or two kinds or more. For example, the copolymer may includethe thermal cross-linking constitutional unit including anon-self-cross-linkable thermal cross-linking group, and the thermalcross linking constitutional unit including a self-cross-linkablecross-linking group as the thermal cross-linking group.

A monomer including a thermal cross-linking group for forming thethermal cross-linking constitutional unit may be used for synthesizingthe copolymer. The monomer including the thermal cross-linking group maybe used singly or in combination of two kinds or more.

The content of the thermal cross-linking constitutional unit in thecopolymer may be determined in the range of about 10% by mol to 90% bymol, and is preferably within a range of about 20% by mol to 80% by molwhen the whole copolymer is regarded as 100% by mol. The low content ofthe thermal cross-linking constitutional unit occasionally maintainsfavorable liquid crystal alignment ability with difficulty by reason ofnot obtaining a sufficient thermosetting property. Also, the highcontent of the thermal cross-linking constitutional unit occasionallydecreases the content of the photo-alignment constitutional unitrelatively to deteriorate sensitivity and allow favorable liquid crystalalignment ability with difficulty.

(3) Another Constitutional Unit

In an embodiment of the present invention, the copolymer may include aconstitutional unit including neither photo-alignment groups nor thermalcross-linking groups other than the photo-alignment constitutional unitand the thermal cross-linking constitutional unit. The inclusion ofanother constitutional unit in the copolymer allows abilities such assolvent solubility, thermal stability, and reactivity to be improved.

Examples of a monomer unit constituting the constitutional unit notincluding photo-alignment groups or thermal cross-linking groups mayinclude acrylate, methacrylate, maleimide, acrylamide, acrylonitrile,maleic anhydride, styrene, and vinyl. Above all, similarly to thethermal cross-linking constitutional unit, acrylate, methacrylate, andstyrene are preferable.

Examples of a monomer for forming such a constitutional unit notincluding photo-alignment groups or thermal cross-linking groups mayinclude an acrylate compound, a methacrylate compound, a maleimidecompound, an acrylamide compound, acrylonitrile, maleic anhydride, astyrene compound, and a vinyl compound.

Examples of the acrylate compound may include methyl acrylate, ethylacrylate, isopropyl acrylate, benzyl acrylate, naphtyl acrylate, anthrylacrylate, anthrylmethyl acrylate, phenyl acrylate, glycidyl acrylate,2,2,2-trifluoroethyl acrylate, tert-butyl acrylate, cyclohexyl acrylate,isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycolacrylate, 2-ethoxyethyl acrylate, 2-aminoethyl acrylate,tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate,2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate,8-methyl-8-tricyclodecyl acrylate, and 8-ethyl-8-tricyclodecyl acrylate.

Examples of the methacrylate compound may include methyl methacrylate,ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphtylmethacrylate, anthryl methacrylate, anthrylmethylmethacrylate,phenylmethacrylate, glycidyl methacrylate, 2,2,2-trifluoroethylmethacrylate, tert-butyl methacrylate, cyclohexyl methacrylate,isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethyleneglycol methacrylate, 2-ethoxyethyl methacrylate, 2-aminomethylmethacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutylmethacrylate, 2-methyl-2-adamantyl methacrylate, γ-butyrolactonemethacrylate, 2-propyl-2-adamantyl methacrylate,8-methyl-8-tricyclodecyl methacrylate and 8-ethyl-8-tricyclodecylmethacrylate.

Examples of the vinyl compound may include methyl vinyl ether, benzylvinyl ether, vinylnaphthalene, vinylcarbazole, allylglycidyl ether,3-ethenyl-7-oxabicyclo[4.1.0]heptane, 1,2-epoxy-5-hexene and1,7-octadiene monoepoxide.

Examples of the styrene compound may include styrene, para-methylstyrene, α-methyl styrene, chlorostyrene, bromostyrene,para-trifluoromethyl styrene, para-trifluoromethyl-α-methyl styrene,4(4-trifluoromethylbenzoyloxy)styrene, para-cetyloxystyrene, andpara-palmitoyloxystyrene.

Examples of the maleimide compound may include maleimide,N-methylmaleimide, N-phenylmaleimide and N-cyclohexylmaleimide.

The constitutional unit not including photo-alignment groups or thermalcross-linking groups in the copolymer may be one kind, or two kinds ormore.

The content of the constitutional unit in the copolymer is preferablywithin a range of about 0% by mol to 50% by mol, and more preferablywithin a range of about 0% by mol to 30% by mol when the whole copolymeris regarded as 100% by mol. The high content of the constitutional unitoccasionally decreases the content of the photo-alignment constitutionalunit and the thermal cross-linking constitutional unit relatively, todeteriorate sensitivity, allow favorable liquid crystal alignmentability with difficulty, allow no sufficient thermosetting property andmaintain favorable liquid crystal alignment ability with difficulty.

(4) Copolymer

The number-average molecular weight of the copolymer is not particularlylimited and may be determined at approximately 3,000 to 200,000, andpreferably within a range of about 4,000 to 100,000. Too largenumber-average molecular weight occasionally deteriorates handleabilityby reason of decreasing solubility in solvent and increasing viscosityto form a uniform film with difficulty. Also, too small number-averagemolecular weight occasionally deteriorates solvent resistance andthermal stability by reason of curing shortage during thermal curing.

Incidentally, the number-average molecular weight may be measured by agel permeation chromatography (GPC) method.

Examples of a synthesis method for the copolymer may include a methodfor copolymerizing a styrene-based monomer including the photo-alignmentgroup and a styrene-based monomer including the thermal cross-linkinggroup.

The synthesis method for the copolymer is not particularly limited, butthe copolymer may be obtained by polymerization in a solvent in which astyrene-based monomer including the photo-alignment group, astyrene-based monomer including the thermal cross-linking group, and apolymerization initiator coexist. On that occasion, the solvent to beused is not particularly limited if it dissolves a styrene-based monomerincluding the photo-alignment group, a styrene-based monomer includingthe thermal cross-linking group and a polymerization initiator.Specifically, the solvent may be the same as the after-mentioned solventused for the thermosetting composition with a photo-alignment property.Also, the temperature during the polymerization reaction may bedetermined at approximately 50° C. to 120° C. The copolymer obtained bythe method is ordinarily in a state of a solution dissolved in thesolvent.

The copolymer obtained by the method may be used directly or used afterbeing purified by the method described below.

That is to say, the solution of the copolymer obtained by the method isprojected into diethyl ether, methanol or water while stirred, andreprecipitated, and then the produced precipitate is filtered, washedand thereafter subjected to drying at room temperature or drying byheating under normal pressure or reduced pressure to obtain powder ofthe copolymer. The polymerization initiator and unreacted monomercoexisting with the copolymer may be removed by this process toconsequently allow purified powder of the copolymer to be obtained. Inthe case of being incapable of sufficient purification in one process,the obtained powder may be redissolved in the solvent to repeat theprocess.

The copolymer may be used in the form of the solution during thesynthesis thereof, in the form of the powder, or in the form of thesolution in which the purified powder is redissolved in theafter-mentioned solvent.

Also, the copolymer may be one kind or a mixture of plural kinds ofcopolymers.

2. Cross-Linking Agent

The thermosetting composition with a photo-alignment property of anembodiment of the present invention preferably contains a cross-linkingagent. The cross-linking agent bonds to the thermal cross-linkingconstitutional unit of the copolymer, and allows thermal stability andsolvent resistance to be improved. Meanwhile, in view of photoreactivityand sensitivity, it is preferable that the thermosetting compositionwith a photo-alignment property of an embodiment of the presentinvention does not contain a cross-linking agent.

Examples of the cross-linking agent may include an epoxy compound, amethylol compound, and an isocyanato compound. Above all, a methylolcompound is preferable.

Examples of the methylol compound may include alkoxymethylatedglycoluril, alkoxymethylated benzoguanamine, and alkoxymethylatedmelamine.

Examples of the alkoxymethylated glycoluril may include1,3,4,6-tetrakis(methoxymethyl)glycoluril,1,3,4,6-tetrakis(butoxymethyl)glycoluril,1,3,4,6-tetrakis(hydroxymethyl)glycoluril, 1,3-bis(hydroxymethyl)urea,1,1,3,3-tetrakis(butoxymethyl)urea, 1,1,3,3-tetrakis(methoxymethyl)urea,1,3-bis(hydroxymethyl)-4,5-dihydroxy-2-imidazolinone and1,3-bis(methoxymethyl)-4,5-dimethoxy-2-imidazolinone. Examples of acommercial product thereof may include a compound such as a glycolurilcompound (trade name CYMEL 1170 and POWDERLINK 1174), methylated urearesin (trade name UFR65) and butylated urea resin (trade name UFR300,U-VAN10S60, U-VAN10R and U-VAN11HV) manufactured by Mitsui Cytec Ltd.,urea/formaldehyde resin (high condensation type, trade name BECKAMINEJ-300S, BECKAMINE P-955, and BECKAMINE N) manufactured by DICCorporation, and a glycoluril compound (trade name NIKALAC MX-270), andan imidazolidine compound (trade name NIKALAC MX-280) manufactured bySANWA CHEMICAL CO., LTD.

Examples of the alkoxymethylated benzoguanamine may includetetramethoxymethylbenzoguanamine. Examples of a commercial productthereof may include products (trade name CYMEL 1123) manufactured byMitsui Cytec Ltd., and (trade name NIKALAC BX-4000, NIKALAC BX-37,NIKALAC BL-60, and NIKALAC BX-55H) manufactured by SANWA CHEMICAL CO.,LTD.

Examples of the alkoxymethylated melamine may includehexamethoxymethylmelamine. Examples of a commercial product thereof mayinclude methoxymethyl type melamine compounds (trade name CYMEL 300,CYMEL 301, CYMEL 303, CYMEL 350, and CYMEL 3745), and butoxymethyl typemelamine compounds (trade name MYCOAT 506, MYCOAT 508, and CYMEL 1156)manufactured by Mitsui Cytec Ltd., and methoxymethyl type melaminecompounds (trade name NIKALAC MW-30, MW-22, MW-11, MS-001, MX-002,MX-730, MX-750, MX-035, MW-390, MW-100LM, and MX-750LM), andbutoxymethyl type melamine compounds (trade name NIKALAC MX-45, MX-410,and MX-302) manufactured by SANWA CHEMICAL CO., LTD.

Also, a cross-linking agent containing plural benzene rings in amolecule may be utilized. Examples of the cross-linking agent containingplural benzene rings in a molecule may include a phenol derivative witha molecular weight of 1200 or less, including two or more of ahydroxymethyl group or an alkoxymethyl group in total, and amelamine-formaldehyde derivative and an alkoxymethylglycolurilderivative including at least two free N-alkoxymethyl groups. The phenolderivative including a hydroxymethyl group may be obtained by reacting aphenol compound not including the corresponding hydroxymethyl group withformaldehyde under a base catalyst.

Also, the cross-linking agent may be a compound obtained by condensingsuch melamine compound, urea compound, glycoluril compound, andbenzoguanamine compound in which a hydrogen atom of an amino group issubstituted with a methylol group or an alkoxymethyl group. Examplesthereof may include a high-molecular-weight compound produced from themelamine compound and the benzoguanamine compound described in U.S. Pat.No. 6,323,310. Examples of a commercial product of the melamine compoundmay include trade name CYMEL 303 (manufactured by Mitsui Cytec Ltd.).Examples of a commercial product of the benzoguanamine compound mayinclude trade name CYMEL 1123 (manufactured by Mitsui Cytec Ltd.).

In addition, a polymer produced by using an acrylamide compound or amethacrylamide compound substituted with a hydroxymethyl group or analkoxymethyl group, such as N-hydroxymethylacrylamide,N-methoxymethylmethacrylamide, N-ethoxymethylacrylamide, andN-butoxymethylmethacrylamide, may be used as the cross-linking agent.

Examples of such a polymer may include poly(N-butoxymethylacrylamide), acopolymer of N-butoxymethylacrylamide and styrene, a copolymer ofN-hydroxymethylmethacrylamide and methyl methacrylate, a copolymer ofN-ethoxymethylmethacrylamide and benzyl methacrylate, and a copolymer ofN-butoxymethylacrylamide, benzyl methacrylate, and 2-hydroxypropylmethacrylate. The weight-average molecular weight of such a polymer iswithin a range of about 1,000 to 500,000, preferably within a range ofabout 2,000 to 200,000, more preferably within a range of about 3,000 to150,000, and further more preferably within a range of about 3,000 to50,000.

These cross-linking agents may be used singly or in combination of twokinds or more.

The content of the cross-linking agent in the thermosetting compositionwith a photo-alignment property of an embodiment of the presentinvention is preferably within a range of about 1 part by mass to 40parts by mass, and more preferably within a range of about 5 parts bymass to 30 parts by mass with respect to 100 parts by mass of thecopolymer. Too small content brings a possibility of deterioratingthermal stability and solvent resistance of a cured film formed from thethermosetting composition with a photo-alignment property to deteriorateliquid crystal alignment ability. Also, too large content occasionallydeteriorates liquid crystal alignment ability and storage stability.

3. Acid or Acid Generator

The thermosetting composition with a photo-alignment property of anembodiment of the present invention may contain an acid or an acidgenerator. An acid or an acid generator allows a thermosetting reactionof the thermosetting composition with a photo-alignment property of anembodiment of the present invention to be promoted.

The acid or the acid generator is not particularly limited if it is asulfonic group-containing compound, hydrochloric acid or a salt thereof,and a compound which is thermally decomposed during drying and thermalcuring of a coating film to generate an acid, namely, a compound whichis thermally decomposed at a temperature of 50° C. to 250° C. togenerate an acid. Examples of such a compound may include hydrochloricacid, and sulfonic acid or hydrates and salts thereof such asmethansulfonic acid, ethansulfonic acid, propansulfonic acid,butansulfonic acid, pentansulfonic acid, octansulfonic acid,benzenesulfonic acid, para-toluenesulfonic acid, camphasulfonic acid,trifluoromethansulfonic acid, para-phenolsulfonic acid,2-naphthalenesulfonic acid, mesitylenesulfonic acid,para-xylene-2-sulfonic acid, meta-xylene-2-sulfonic acid,4-ethylbenezenesulfonic acid, 1H, 1H, 2H, 2H-perfluorooctansulfonicacid, perfluoro(2-ethoxyethane)sulfonic acid, pentafluoroethanesulfonicacid, nonafluorobutane-1-sulfonic acid, and dodecylbenezenesulfonicacid. Examples of a compound which generates an acid by heat may includebis (tosyloxy) ethane, bis(tosyloxy)propane, bis(tosyloxy)butane,para-nitrobenzyl tosylate, ortho-nitrobenzyl tosylate,1,2,3-phenylenetris(methylsulfonate), para-toluenesulfonicacidpyridiniumsalt, para-toluenesulfonic acid morphonium salt,para-toluenesulfonic acid ethyl ester, para-toluenesulfonic acid propylester, para-toluenesulfonic acid butyl ester, para-toluenesulfonic acidisobutyl ester, para-toluenesulfonic acid methyl ester,para-toluenesulfonic acid phenethyl ester, cyanomethylpara-toluenesulfonate, 2,2,2-trifluoroethyl para-toluenesulfonate,2-hydroxybutyl para-tosylate, and N-ethyl-4-toluenesulfonamide. Also, acompound described in WO 2010/150748 may be used as the compound whichgenerates an acid by heat.

The content of the acid or the acid generator in the thermosettingcomposition with a photo-alignment property of an embodiment of thepresent invention is preferably within a range of about 0.01 part bymass to 20 parts by mass, more preferably within a range of about 0.05part by mass to 10 parts by mass, and further more preferably within arange of about 0.1 part by mass to 5 parts by mass with respect to 100parts by mass of the copolymer. The content of the acid or the acidgenerator within the range allows sufficient thermosetting property andsolvent resistance, and high sensitivity to light irradiation. On theother hand, too large content occasionally deteriorates storagestability of the thermosetting composition with a photo-alignmentproperty.

4. Sensitizer

The thermosetting composition with a photo-alignment property of anembodiment of the present invention may contain a sensitizer. Asensitizer allows a photoreaction such as a photo-dimerization reactionand a photo-isomerization reaction to be promoted.

Examples of the sensitizer may include benzophenone, anthracene,anthraquinone, thioxanthone, and derivatives of these, and a nitrophenylcompound. Among these, benzophenone derivatives and a nitrophenylcompound are preferable. Examples of the preferable compound may includeN,N-diethylaminobenzophenone, 2-nitrofluorene, 2-nitrofluorenone,5-nitroacenaphthene, and 4-nitrobiphenyl. In particular,N,N-diethylaminobenzophenone, which is a derivative for benzophenone, ispreferable. The sensitizer may be used singly or in combination of twokinds or more of compounds together.

The content of the sensitizer in the thermosetting composition with aphoto-alignment property of an embodiment of the present invention ispreferably within a range of about 0.1 part by mass to 20 parts by mass,and more preferably within a range of about 0.2 part by mass to 10 partsby mass with respect to 100 parts by mass of the copolymer. Too smallcontent occasionally does not allow a sufficient effect of thesensitizer, and too large content occasionally brings the deteriorationof transmittance and roughness of a coating film.

5. Solvent

The thermosetting composition with a photo-alignment property of anembodiment of the present invention is mainly used in a solution stateof being dissolved in a solvent.

The solvent is not particularly limited if it may dissolve each of thecomponents, and examples thereof may include ethylene glycol monomethylether, ethylene glycolmonoethyl ether, methyl Cellosolve acetate, ethylCellosolve acetate, diethylene glycol monomethyl ether, diethyleneglycol monoethyl ether, propylene glycol, propylene glycol monomethylether, propylene glycol monomethyl ether acetate, propylene glycolpropyl ether acetate, ethylene glycol dimethyl ether, propylene glycoldimethyl ether, toluene, xylene, methyl ethyl ketone, cyclopentanone,cyclohexanone, 2-butanone, 3-methyl-2-pentanone, 2-pentanone,2-heptanone, γ-butyrolactone, ethyl 2-hydroxypropionate, ethyl2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate,methyl 2-hydroxy-3-methylbutanoic acid, methyl 3-methoxypropionate,ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate,butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide,N,N-dimethylacetamide, and N-methylpyrrolidone. The solvent may be usedin one kind singly or in combination of two kinds or more.

Above all, propylene glycol monomethyl ether, propylene glycolmonomethyl ether acetate, ethylene glycol dimethyl ether, propyleneglycol dimethyl ether, methyl ethyl ketone, cyclohexanone, 2-heptanone,propylene glycol propyl ether, propylene glycol propyl ether acetate,ethyl lactate, butyl lactate, methyl 3-methoxypropionate, ethyl3-methoxypropionate, ethyl 3-ethoxypropionate, and methyl3-ethoxypropionate are preferable by reason of favorable film formationand high safety.

6. Addition Agent

The thermosetting composition with a photo-alignment property of anembodiment of the present invention may contain a silane coupling agent,a surface-active agent, a rheology adjustor, a pigment, dyestuffs, astorage stabilizer, an antifoaming agent and an antioxidant as requiredas long as the effect of an embodiment of the present invention is notdeteriorated.

7. Thermosetting Composition with Photo-Alignment Property

The thermosetting composition with a photo-alignment property of anembodiment of the present invention is ordinarily used as a solution inwhich each of the components is dissolved in a solvent. The ratio ofsolid content in the thermosetting composition with a photo-alignmentproperty of an embodiment of the present invention is not particularlylimited if each of the components is uniformly dissolved in a solvent,and is within a range of about 0.1% by mass to 80% by mass, preferablywithin a range of about 0.5% by mass to 60% by mass, and more preferablywithin a range of about 0.5% by mass to 40% by mass. Too small ratio ofsolid content occasionally allows liquid crystal alignment ability andthermosetting property with difficulty. Also, too large ratio of solidcontent increases the viscosity of the thermosetting composition with aphoto-alignment property to forma uniform film with difficulty.

Incidentally, the solid content signifies such that the solvent isremoved from all components of the thermosetting composition with aphoto-alignment property.

A method for preparing the thermosetting composition with aphoto-alignment property of an embodiment of the present invention isnot particularly limited but is preferably a method for mixing thecopolymer, the cross-linking agent, the sensitizer and other additionagents to thereafter add the acid or the acid generator for the reasonthat storage stability is improved. Incidentally, in the case of addingthe acid or the acid generator first, the compound which is thermallydecomposed during drying and thermal curing of a coating film togenerate an acid is preferably used as the acid or the acid generator.

A solution of the copolymer obtained by a polymerization reaction in thesolvent may be used directly in the preparation of the thermosettingcomposition with a photo-alignment property of an embodiment of thepresent invention. In this case, as described above, the cross-linkingagent, the sensitizer and other addition agents are projected into thesolution of the copolymer to obtain the uniform solution, to which theacid or the acid generator is thereafter added. On this occasion, asolvent may be further added for the purpose of concentrationadjustment. Then, the solvent used in the production process of thecopolymer and the solvent used for concentration adjustment of thethermosetting composition with a photo-alignment property may be thesame or different.

Also, the adjusted solution of the thermosetting composition with aphoto-alignment property is preferably used after being filtered byusing a filter with a pore diameter of approximately 0.2 μm.

8. Uses

Examples of the uses of the thermosetting composition with aphoto-alignment property of an embodiment of the present invention mayinclude an alignment layer of various optical elements such as aretardation plate, and an alignment layer of a liquid crystal displayelement. Also, the thermosetting composition with a photo-alignmentproperty of an embodiment of the present invention may be used for aninsulating film and a protective film in various devices such as aliquid crystal display element, an organic EL element, TFT, and a colorfilter; examples thereof may include an insulating film of an organic ELelement, an interlayer insulating film of TFT, and an overcoat layer ofa color filter.

B. Alignment Layer

An alignment layer of an embodiment of the present invention comprises acopolymer including a photo-alignment constitutional unit represented bythe formula (1) and a cross-linking structure, and the alignment layercomprises a photo-dimerization structure or a photo-isomerizationstructure of a photo-alignment group in the photo-alignmentconstitutional unit.

Here, the cross-linking structure signifies a three-dimensional networkstructure. The after-mentioned structure such that photo-alignmentgroups are cross-linked by a photo-dimerization reaction is not includedin the cross-linking structure.

According to an embodiment of the present invention, the alignment layerincludes the predetermined copolymer and the predeterminedphoto-dimerization structure or photo-isomerization structure so thatfavorable liquid crystal alignment ability, thermal stability, andsolvent resistant may be obtained.

The copolymer includes the photo-alignment constitutional unitrepresented by the formula (1), and a cross-linking structure, that maybe formed by heat-curing the copolymer containing the photo-alignmentconstitutional unit represented by the formula (1) and a thermalcross-linking constitutional unit, which are described in the “A.Thermosetting composition with photo-alignment property”. Thecross-linking structure is a three-dimensional network structure and astructure such that a thermal cross-linking group of a thermalcross-linking constitutional unit is cross-linked. In the case thethermosetting composition with a photo-alignment property contains across-linking agent, a thermal cross-linking group of a thermalcross-linking constitutional unit ordinarily bonds to the cross-linkingagent. Incidentally, in the case the thermal cross-linkingconstitutional unit includes a self-cross-linkable cross-linking groupas the thermal cross-linking group, the self-cross-linkablecross-linking group also bonds to the cross-linking agent. Also, in thecase the copolymer contains the thermal cross-linking constitutionalunit including a nonself-cross-linkable thermal cross-linking group andthe thermal cross-linking constitutional unit including aself-cross-linkable cross-linking group as the thermal cross-linkinggroup, the nonself-cross-linkable thermal cross-linking group bonds tothe self-cross-linkable cross-linking group. Also, in the case thethermal cross-linking constitutional unit includes a self-cross-linkablecross-linking group as the thermal cross-linking group, thecross-linking group is self-cross-linked. Accordingly, the cross-linkingstructure is a structure such that the thermal cross-linking group andthe cross-linking agent are cross-linked by heating, a structure suchthat the nonself-cross-linkable thermal cross-linking group and theself-cross-linkable cross-linking group are cross-linked by heating, ora structure such that the self-cross-linkable cross-linking groups arecross-linked by heating.

For example, in the case the cross-linking agent ishexamethoxymethylmelamine, the cross-linking structure is a structuredescribed below. Incidentally, in the following formula, each sign isthe same as in the formula (1).

Incidentally, each constitutional unit of the copolymer is described indetail in the “A. Thermosetting composition with photo-alignmentproperty”; therefore, the description herein is omitted.

It may be confirmed by taking and analyzing a material from thealignment layer that the alignment layer contains the copolymer. Amethod of NMR, IR, GC-MS, XPS, TOF-SIMS, and a combination of these maybe applied to an analytical method.

Also, the alignment layer of an embodiment of the present inventioncomprises a photo-dimerization structure or a photo-isomerizationstructure of a photo-alignment group in the photo-alignmentconstitutional unit represented by the formula (1).

The photo-dimerization structure is a structure such that thephoto-alignment groups of the photo-alignment constitutional unitrepresented by the formula (1) are cross-linked by a photo-dimerizationreaction, and is a structure including a cyclopropane skeleton.

The photo-dimerization reaction is the reaction described below and areaction such that an olefin structure contained in the photo-alignmentgroup forms a cyclopropane skeleton by a photoreaction. In accordancewith kinds of the photo-alignment group, Xa to Xd and Xa′ to Xd′ varies.

The photo-dimerization structure is preferably a photo-dimerizationstructure of a cinnamoyl group. Specifically, the photo-dimerizationstructure is preferably a structure such that the cinnamoyl groupsdescribed in the “A. Thermosetting composition with photo-alignmentproperty” are cross-linked by a photo-dimerization reaction. Above all,the alignment layer preferably includes the photo-dimerization structurerepresented by the following formulae (4-1) and (4-2) Incidentally, inthe following formula, each sign is the same as in the formulae (1-6)and (1-4).

In the case the alignment layer includes the photo-dimerizationstructure represented by the formulae (4-1) and (4-2), many aromaticrings are disposed and many π electrons are contained. Thus, it isconceived that an affinity with a liquid crystal layer disposed on thealignment layer becomes so high as to improve liquid crystal alignmentability and adhesion properties to the liquid crystal layer.

Also, the photo-isomerization structure is a structure such that thephoto-alignment group of the photo-alignment constitutional unitrepresented by the formula (1) is isomerized by a photo-isomerizationreaction. For example, in the case of a cis-trans isomerizationreaction, the photo-isomerization structure may be any of a structuresuch that a cis body changes to a trans body and a structure such that atrans body changes to a cis body.

For example, in the case the photo-alignment group is a cinnamoyl group,the photo-isomerization reaction is the reaction described below and areaction such that an olefin structure contained in the photo-alignmentgroup forms a cis body or a trans body by a photoreaction. In accordancewith kinds of the photo-alignment group, Xa to Xd varies.

The photo-isomerization structure is preferably a photo-isomerizationstructure of a cinnamoyl group. Specifically, the photo-isomerizationstructure is preferably a structure such that the cinnamoyl groupdescribed in the “A. Thermosetting composition with photo-alignmentproperty” is isomerized by a photo-isomerization reaction. In this case,the photo-isomerization structure may be any of a structure such that acis body changes to a trans body and a structure such that a trans bodychanges to a cis body. Above all, the alignment layer preferablyincludes the photo-isomerization structure, which is represented by thefollowing formula, of a cinnamoyl group represented by the formula(1-3).

Incidentally, it may be analyzed by NMR or IR that the alignment layerincludes the photo-dimerization structure or photo-isomerizationstructure.

Also, the alignment layer may contain a cross-linking agent, an acid oran acid generator, a sensitizer, and another addition agent.Incidentally, these addition agents are the same as those described inthe “A. Thermosetting composition with photo-alignment property”.

Other features such as a formation method and a film thickness of thealignment layer are the same as those of the alignment layer in theafter-mentioned substrate with the alignment layer; therefore, thedescription herein is omitted.

C. Substrate with Alignment Layer

A substrate with an alignment layer of an embodiment of the presentinvention comprises a substrate, and an alignment layer formed from thethermosetting composition with a photo-alignment property or thealignment layer described above, disposed on the substrate.

FIG. 1 is a schematic sectional view showing an example of the substratewith an alignment layer of an embodiment of the present invention. In asubstrate with an alignment layer 1 exemplified in FIG. 1, an alignmentlayer 3 is disposed on a substrate 2, and the alignment layer 3 is suchas to be formed from the thermosetting composition with aphoto-alignment property described above.

According to an embodiment of the present invention, the alignment layeris such as to be formed from the thermosetting composition with aphoto-alignment property or the alignment layer described above, so asto allow excellent liquid crystal alignment ability, adhesion propertiesto a liquid crystal layer, thermal stability, and solvent resistance tobe obtained.

Each constitution in the substrate with an alignment layer of anembodiment of the present invention is hereinafter described.

1. Alignment Layer

The alignment layer in an embodiment of the present invention is such asto be formed from the thermosetting composition with a photo-alignmentproperty or the alignment layer described above, and has the function ofaligning liquid crystal molecules.

Here, the alignment layer formed from the thermosetting composition witha photo-alignment property signifies an alignment layer obtained in sucha manner that a film containing the thermosetting composition with aphoto-alignment property is heat-cured and photo-aligned.

That is to say, in the formation of the alignment layer, first, thethermosetting composition with a photo-alignment property is applied ona substrate, dried and heated to form a cured film. Next, the cured filmis irradiated with polarized ultraviolet rays to form the alignmentlayer.

An application method of the thermosetting composition with aphoto-alignment property is not particularly limited if it is a methodsuch as to allow a uniform film on the substrate to be formed, andexamples thereof may include a spin coat method, a roll coat method, arod bar coat method, a spray coat method, an air-knife coat method, aslot die coat method, a wire bar coat method, a flow coat method and anink jet method.

Tools such as a hot plate and an oven may be used for drying a coatingfilm. The temperature may be determined at approximately 30° C. to 160°C., and preferably within a range of about 50° C. to 140° C. The timemay be determined at approximately 20 seconds to 60 minutes, andpreferably within a range of about 30 seconds to 10 minutes.

Tools such as a hot plate and an oven may be also used for heat-curingthe coating film. The temperature may be determined at approximately 30°C. to 250° C. The time may be determined at approximately 20 seconds to60 minutes. Also, drying and heat-curing of the coating film may beperformed simultaneously or separately.

The film thickness of the cured film obtained by heat-curing thethermosetting composition with a photo-alignment property is properlyselected in accordance with uses, and may be determined at approximately0.05 μm to 30 μm. Incidentally, too thin film thickness of the curedfilm occasionally does not allow sufficient liquid crystal alignmentability.

The obtained cured film may be irradiated with polarized ultravioletrays and thereby photo-dimerized or photo-isomerized to developanisotropy. The wavelength of the polarized ultraviolet rays isordinarily within a range of about 150 nm to 450 nm. Also, theirradiation direction of the polarized ultraviolet rays may be avertical or an oblique direction to a substrate plane.

Incidentally, it may be confirmed by taking and analyzing a materialfrom the alignment layer that the alignment layer is formed from thethermosetting composition with a photo-alignment property. A method ofNMR, IR, GC-MS, XPS, TOF-SIMS, and a combination of these may be appliedto an analytical method.

2. Substrate

A substrate used for an embodiment of the present invention supports thealignment layer.

The substrate is not particularly limited and is properly selected inaccordance with uses. Examples of a material for the substrate mayinclude glass and quartz, resins such as polyethylene terephthalate,polycarbonate, triacetylcellulose, polyester, polysulfone, polyethersulfone, cyclopolyolefin, and acryl, metals such as aluminum, andceramics such as silicon and silicon nitride. Also, the substrate may besubjected to surface treatment.

The substrate may have flexibility or not, which is properly selected inaccordance with uses.

3. Conductive Layer

In an embodiment of the present invention, a conductive layer may beformed between the substrate and the alignment layer. The conductivelayer functions as an electrode of various kinds of devices, forexample. Examples of a material for the conductive layer may includetransparent conductive materials such as ITO and IZO, and metallicmaterials such as aluminum, molybdenum and chromium.

4. Uses

Examples of the uses of the substrate with an alignment layer of anembodiment of the present invention may include various optical elementssuch as a retardation plate, a liquid crystal display element, and alight emitting element.

D. Retardation Plate

A retardation plate of an embodiment of the present invention comprisesthe substrate with an alignment layer described above and a retardationlayer disposed on the alignment layer of the substrate with thealignment layer.

FIG. 2 is a schematic sectional view showing an example of theretardation plate in an embodiment of the present invention. In aretardation plate 10 exemplified in FIG. 2, an alignment layer 12 isdisposed on a substrate 11 and a retardation layer 13 is disposed on thealignment layer 12. The alignment layer 12 is such as to be formed fromthe thermosetting composition with a photo-alignment property or thealignment layer described above, and the retardation layer 13corresponds to a liquid crystal layer.

The retardation layer may be obtained in such a manner that a liquidcrystal composition is applied on the alignment layer and heated up tophase transition temperature of the liquid crystal composition, andliquid crystal molecules are aligned by the alignment layer and cured.

The liquid crystal composition contains at least a liquid crystalcompound and ordinarily further contains a solvent. The liquid crystalcomposition may further contain another component as long as thealignment of the liquid crystal compound is not hindered.

A liquid crystal composition generally used for a retardation layer maybe used as the liquid crystal composition used for the retardationlayer. Examples of the liquid crystal composition may include a liquidcrystal composition including alignment properties such as horizontalalignment, cholesteric alignment, vertical alignment, and hybridalignment, and the liquid crystal composition is properly selected inaccordance with a combination with the alignment layer and a desiredretardation.

Above all, the liquid crystal compound is preferably a polymerizableliquid crystal compound including a polymerizable group. The reasontherefor is to allow the polymerizable liquid crystal compounds to becross-linked and to increase stability of the retardation plate.

Also, the film thickness and formation method of the retardation layermay be the same as those of a general retardation layer.

The retardation plate may have flexibility or not.

E. Device

A device of an embodiment of the present invention comprises analignment layer formed from the thermosetting composition with aphoto-alignment property or the alignment layer described above.

The device is not particularly limited if it is such as to include thealignment layer, and examples thereof may include various opticalelements such as a retardation plate, a liquid crystal display element,and a light emitting element.

The device is hereinafter described while divided into a retardationplate and a liquid crystal display element.

1. Retardation Plate

A retardation plate in an embodiment of the present invention comprisesa substrate, an alignment layer formed from the thermosettingcomposition with a photo-alignment property or the alignment layerdescribed above, disposed on the substrate, and a retardation layerdisposed on the alignment layer.

Incidentally, the retardation layer is described in the “D. Retardationplate”; therefore, the description herein is omitted.

A conductive layer may be formed between the substrate and the alignmentlayer. Incidentally, the substrate, the alignment layer and theconductive layer are the same as the substrate, the alignment layer andthe conductive layer in the “C. Substrate with alignment layer”;therefore, the description herein is omitted.

The retardation plate may have flexibility or not.

2. Liquid Crystal Display Element

A liquid crystal display element in an embodiment of the presentinvention has two embodiments. The liquid crystal display element ishereinafter described while divided into each of the embodiments.

(1) First Embodiment

The first embodiment of the liquid crystal display element in anembodiment of the present invention includes a first substrate with analignment layer in which a first alignment layer is disposed on a firstsubstrate, a second substrate with an alignment layer in which a secondalignment layer is disposed on a second substrate, and a liquid crystallayer disposed between the first substrate with an alignment layer andthe second substrate with an alignment layer, and the first alignmentlayer and the second alignment layer are such as to be formed from thethermosetting composition with a photo-alignment property, or thealignment layer described above.

FIG. 3 is a schematic sectional view showing an example of the liquidcrystal display element in an embodiment of the present invention. Aliquid crystal display element 20 exemplified in FIG. 3 comprises afirst substrate with an alignment layer 21 a, a second substrate with analignment layer 21 b, and a liquid crystal layer 25 disposed between thefirst substrate with an alignment layer 21 a and the second substratewith an alignment layer 21 b. In the first substrate with an alignmentlayer 21 a, a first electrode 23 a and a first alignment layer 24 a aresequentially laminated on a first substrate 22 a; in the secondsubstrate with an alignment layer 21 b, a second electrode 23 b and asecond alignment layer 24 b are sequentially laminated on a secondsubstrate 22 b. The first alignment layer 24 a and the second alignmentlayer 24 b are such as to be formed from the thermosetting compositionwith a photo-alignment property or the alignment layer described above.

A liquid crystal composition generally used for a liquid crystal layermay be used as the liquid crystal composition used for the liquidcrystal layer. For example, nematic liquid crystal and smectic liquidcrystal may be used. Also, the film thickness and formation method ofthe liquid crystal layer may be the same as those of a general liquidcrystal layer.

Also, a conductive layer is ordinarily formed as an electrode, at leasteither between the first substrate and the alignment layer or betweenthe second substrate and the alignment layer.

Incidentally, the first substrate, the second substrate, the alignmentlayer, and the conductive layer are the same as the substrate, thealignment layer, and the conductive layer in the “C. Substrate withalignment layer”; therefore, the description herein is omitted.

Also, other constitutions of the liquid crystal display element may bethe same as the constitutions of a general liquid crystal displayelement.

(2) Second Embodiment

The second embodiment of the liquid crystal display element in anembodiment of the present invention comprises the retardation plate.

The constitutions of the liquid crystal display element may be the sameas the constitutions of a general liquid crystal display element. Forexample, the retardation plate may be disposed outside the substrateconstituting the liquid crystal display element, or the substrateconstituting the liquid crystal display element may also serve as thesubstrate constituting the retardation plate, and the alignment layerand the retardation layer may be disposed inside the substrate.

The present disclosure is not limited to the embodiments. Theembodiments are exemplification, and any is included in the technicalscope of the present disclosure if it has substantially the sameconstitution as the technical idea described in the claim of the presentdisclosure and offers similar operation and effect thereto.

EXAMPLES

Embodiments of the present invention are described in further detailwith reference to examples and comparative examples hereinafter.

[Synthesis Example a] Synthesis of Thermal Cross-Linkable Monomer 1

The weight of 20.0 g (118 mmol) of para-acetoxystyrene is dissolved in80 mL of ethyl acetate in a 200-mL flask under a nitrogen atmosphere,and 9.08 g (47.1 mmol) of sodium methoxide was slowly dropped thereintoover approximately 30 minutes. After stirring for one and a half hours,the finish of the reaction was confirmed by TLC to extract by ethylacetate, thereafter washed in 1N-hydrochloric acid, pure water, andsaturated salt solution, and dried by sodium sulfate. The solvent wasdistilled off and dried to thereby obtain a thermal cross-linkablemonomer 1.

[Synthesis Example b] Synthesis of Thermal Cross-Linkable Monomer 2

The thermal cross-linkable monomer 1 was obtained in the same manner asin Synthesis Example a. In a 200-mL flask, 14.0 g (118 mmol) of thethermal cross-linkable monomer 1 was dissolved in 100 ml ofdimethylformamide under a nitrogen atmosphere and ice cooling, and 7.07g (177 mmol) of sodium hydroxide was added thereto and stirred for 15minutes to thereafter drop 10.5 g (130 mmol) of 2-chloroethanol takingapproximately 10 minutes. After stirring for 16 hours, the finish of thereaction was confirmed by TLC to extract by ethyl acetate, thereafterwashed in saturated hydrogen carbonate aqueous solution, 1N-hydrochloricacid, pure water, and saturated salt solution, and dried by sodiumsulfate. The solvent was distilled off and dried to thereby obtain athermal cross-linkable monomer 2.

[Synthesis Example c] Synthesis of Self-Cross-Linkable ThermalCross-Linkable Monomer 3

The weight of 20.0 g (118 mmol) of para-acetoxystyrene was dissolved in80 mL of ethyl acetate in a 200-mL flask under a nitrogen atmosphere,and 9.08 g (47.1 mmol) of sodium methoxide was slowly dropped thereintoover approximately 30 minutes. After stirring for one and a half hoursand confirming the finish of the reaction by TLC, 56.0 mL (944 mmol) of37%-formalin aqueous solution was slowly added to this solution underroom temperature. In addition, this solution was stirred under anitrogen atmosphere at 40° C. for 24 hours, and thereafter projectedinto 200 mL of water in a beaker. To this solution, 2.0-wt % acetic acidaqueous solution was slowly added till reaching pH 5.0 while cooled inan ice bath. A precipitate was filtered out, sufficiently washed inwater, thereafter dried, and filtered by column chromatography tothereby obtain a self-cross-linkable thermal cross-linkable monomer 3.

[Synthesis Example d] Synthesis of Self-Cross-Linkable ThermalCross-Linkable Monomer 4

The weight of 20.0 g (118 mmol) of para-acetoxystyrene is dissolved in80 mL of ethyl acetate in a 200-mL flask under a nitrogen atmosphere,and 9.08 g (47.1 mmol) of sodium methoxide was slowly dropped thereintoover approximately 30 minutes. After stirring for one and a half hours,the finish of the reaction was confirmed by TLC to extract by ethylacetate, thereafter washed in 1N-hydrochloric acid, pure water, andsaturated salt solution, and dried by sodium sulfate. The solvent wasdistilled off and dried to thereby obtain a self-cross-linkable monomerderivative 1.

The weight of 12 g (100 mmol) of the self-cross-linkable monomerderivative 1, 16.1 g (110 mmol) of adipic acid and 1.2 g (9.8 mmol) ofdimethylaminopyridine were dissolved in 130 ml of dichloromethane in a500-mL flask, and 22.6 g (110 mmol) of N,N′-dicyclohexylcarbodiimidedissolved in 40 ml of dichloromethane was dropped thereinto overapproximately 10 minutes. After stirring for 15 hours, the reactionsolution was cooled to filter out a precipitate. The solvent wasdistilled off to add methanol, and a self-cross-linkable monomerderivative 2 was obtained by recrystallization thereof.

Subsequently, 13.82 g (50 mmol) of the self-cross-linkable monomerderivative 2, 5.5 g (50 mmol) of hydroquinone and 0.176 g (1.47 mmol) ofdimethylaminopyridine were dissolved in 50 ml of dichloromethane in a300-mL flask under ice cooling, and 11.3 g (55 mmol) ofN,N′-dicyclohexylcarbodiimide dissolved in 10 ml of dichloromethane wasdropped thereinto over approximately 10 minutes. After stirring for 15hours, the reaction solution was cooled to filter out a precipitate. Thesolvent was distilled off to add methanol, and a self-cross-linkablemonomer derivative 3 was obtained by recrystallization thereof.

The weight of 3.68 g (10 mmol) of the self-cross-linkable monomerderivative 3 was added to a solution comprising 20 mL of 10% byweight-potassium hydroxide aqueous solution and 20 mL of ethanol,stirred, and dissolved at room temperature. To this solution, 7.0 mL (80mmol) of 37%-formalin aqueous solution was slowly added under roomtemperature. In addition, this solution was stirred under a nitrogenatmosphere at 40° C. for 24 hours, and thereafter projected into 200 mLof water in a beaker. To this solution, 2.0-wt % acetic acid aqueoussolution was slowly added till reaching pH 5.0 while cooled in an icebath. A precipitate was filtered out, sufficiently washed in water,thereafter dried, and purified by column chromatography to therebyobtain a self-cross-linkable thermal cross-linkable monomer 4.

[Synthesis Example 1] Synthesis of Photo-Alignment Monomer 1

The weight of 14.7 g (80 mmol) of 4-bromostyrene, 0.18 g (800 μmol) ofpalladium chloride, 0.98 g (3.2 mmol) of tris(2-tolyl)phosphine and 32.4g (320 mmol) of triethylamine were dissolved in 135 mL ofdimethylacetamide in a 300-mL flask. Next, this solution was added to8.3 g (97 mmol) of methyl acrylate mixed solution by a syringe andstirred. This mixed solution was further heated and stirred at 120° C.for 3 hours. After confirming the finish of the reaction by TLC, thereaction solution was cooled to room temperature. After filtering out aprecipitate, filtrate was poured into 300 mL of 1N-hydrochloric acidaqueous solution to recover the precipitate. These precipitates wererecrystallized by a 1:1 (mass ratio) solution of ethyl acetate andhexane to thereby obtain a photo-alignment monomer 1.

[Synthesis Example 2] Synthesis of Photo-Alignment Monomer 2

A photo-alignment monomer 2 was obtained by replacing methyl acrylate inSynthesis Example 1 with the equal mol amount of phenyl acrylate, and byreacting in the same manner as in Synthesis Example 1.

[Synthesis Example 3] Synthesis of Photo-Alignment Monomer 3

The weight of 20.15 g (136 mmol) of 4-vinyl benzoate, 21.0 g (118 mmol)of trans-4-methyl hydroxycinnamate, and 0.458 g (3.82 mmol) ofdimethylaminopyridine were dissolved in 130 ml of dichloromethane in a300-mL flask under ice cooling, and 28.0 g (136 mmol) ofN,N′-dicyclohexylcarbodiimide dissolved in 40 ml of dichloromethane wasdropped thereinto over approximately 10 minutes. After stirring for 15hours, the reaction solution was cooled to filter out a precipitate. Thesolvent was distilled off to add methanol, and a photo-alignment monomer3 was obtained.

[Synthesis Example 4] Synthesis of Photo-Alignment Monomer 4

The weight of 15.4 g (50 mmol) of the photo-alignment monomer 3 wasdissolved in 200 mL of methanol in a 500-mL flask under a nitrogenatmosphere, and 8.3 g (60 mmol) of potassium carbonate was addedthereto, and stirred through the night. The finish of the reaction wasconfirmed by TLC, and a precipitate was filtered and thereafterconcentrated. The concentrate was extracted by ethyl acetate, thereafterwashed in 1N-hydrochloric acid, pure water, and saturated salt solution,and dried by sodium sulfate. The solvent was distilled off and dried tothereby obtain a styrene derivative 1.

Subsequently, a photo-alignment monomer 4 was obtained by replacing4-vinyl benzoate in Synthesis Example 3 with the equal mol amount of thestyrene derivative 1, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of 4-cyanophenol, and bycondensing in the same manner as in Synthesis Example 3.

[Synthesis Example 5] Synthesis of Photo-Alignment Monomer 5

The thermal cross-linkable monomer 1 was obtained in the same manner asin Synthesis Example a. In a 500-mL flask, 12 g (100 mmol) of thethermal cross-linkable monomer 1, 11.0 g (110 mmol) of succinicanhydride, and 1.2 g (9.8 mmol) of 4-dimethylaminopyridine were added tosufficiently dry the system. To this system, 11.2 g (110 mmol) oftriethylamine and 200 mL of tetrahydrofuran were added, and reactedunder reflux for 5 hours. After finishing the reaction, dilutehydrochloric acid was added, and an organic layer obtained by extractingwith ethyl acetate was washed in water, dried by magnesium sulfate,thereafter concentrated and recrystallized by ethanol to thereby obtaina styrene derivative 2.

Subsequently, a photo-alignment monomer 5 was obtained by replacing4-vinyl benzoate in Synthesis Example 3 with the equal mol amount of thestyrene derivative 2, and by condensing in the same manner as inSynthesis Example 3.

[Synthesis Example 6] Synthesis of Photo-Alignment Monomer 6

A styrene derivative 3 was obtained by replacing the photo-alignmentmonomer 3 in Synthesis Example 4 with the equal mol amount of thephoto-alignment monomer 5, and by deprotecting in the same manner as inSynthesis Example 4.

Subsequently, a photo-alignment monomer 6 was obtained by replacing4-vinyl benzoate in Synthesis Example 3 with the equal mol amount of thestyrene derivative 3, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of 4-methoxyphenol, and bycondensing in the same manner as in Synthesis Example 3.

[Synthesis Example 7] Synthesis of Photo-Alignment Monomer 7

A styrene derivative 4 was obtained by replacing 4-vinyl benzoate inSynthesis Example 3 with the equal mol amount of the thermalcross-linkable monomer 1, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of adipic acid, and bycondensing in the same manner as in Synthesis Example 3.

Subsequently, a photo-alignment monomer 7 was obtained by replacing4-vinyl benzoate in Synthesis Example 3 with the equal mol amount of thestyrene derivative 4, and by condensing in the same manner as inSynthesis Example 3.

[Synthesis Example 8] Synthesis of Photo-Alignment Monomer 8

A photo-alignment monomer 8 was obtained by replacing 4-vinyl benzoatein Synthesis Example 3 with the equal mol amount of the styrenederivative 2, replacing trans-4-methyl hydroxycinnamate in SynthesisExample 3 with the equal mol amount of methyl ferulate, and bycondensing in the same manner as in Synthesis Example 3.

[Synthesis Example 9] Synthesis of Photo-Alignment Monomer 9

A photo-alignment monomer 9 was obtained by replacing 4-vinyl benzoatein Synthesis Example 3 with the equal mol amount of the thermalcross-linkable monomer 1, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of trans-cinnamic acid,and by condensing in the same manner as in Synthesis Example 3.

[Synthesis Example 10] Synthesis of Photo-Alignment Monomer 10

A photo-alignment monomer 10 was obtained by replacing 4-vinyl benzoatein Synthesis Example 3 with the equal mol amount of the thermalcross-linkable monomer 1, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of 4-methoxycinnamic acid,and by condensing in the same manner as in Synthesis Example 3.

[Synthesis Example 11] Synthesis of Photo-Alignment Monomer 11

A styrene derivative 5 was obtained by replacing trans-4-methylhydroxycinnamate in Synthesis Example 3 with the equal mol amount ofethylene glycol, and by condensing in the same manner as in SynthesisExample 3.

Subsequently, a photo-alignment monomer 11 was obtained by replacing4-vinyl benzoate in Synthesis Example 3 with the equal mol amount of thestyrene derivative 5, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of trans-cinnamic acid,and by condensing in the same manner as in Synthesis Example 3.

[Synthesis Example 12] Synthesis of Photo-Alignment Monomer 12

A styrene derivative 6 was obtained by replacing trans-4-methylhydroxycinnamate in Synthesis Example 3 with the equal mol amount of1,4-butanediol, and by condensing in the same manner as in SynthesisExample 3.

Subsequently, a photo-alignment monomer 12 was obtained by replacing4-vinyl benzoate in Synthesis Example 3 with the equal mol amount of thestyrene derivative 6, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of trans-cinnamic acid,and by condensing in the same manner as in Synthesis Example 3.

[Synthesis Example 13] Synthesis of Photo-Alignment Monomer 13

A photo-alignment monomer 13 was obtained by replacing 4-vinyl benzoatein Synthesis Example 3 with the equal mol amount of the thermalcross-linkable monomer 2, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of trans-cinnamic acid,and by condensing in the same manner as in Synthesis Example 3.

[Synthesis Example 14] Synthesis of Photo-Alignment Monomer 14

The weight of 14.8 g (100 mmol) of trans-cinnamic acid and 20.2 g (200mmol) of triethylamine were dissolved in 200 ml of dichloromethane in a300-mL flask and stirred in an ice bath for 15 minutes. To this system,16.7 g (110 mmol) of 4-(chloromethyl) styrene was slowly added andstirred for 18 hours. After finishing the reaction, dilute hydrochloricacid was added, and an organic layer obtained by extracting with ethylacetate was washed in water, dried by magnesium sulfate, thereafterconcentrated and recrystallized by ethanol to thereby obtain aphoto-alignment monomer 14.

[Synthesis Example 15] Synthesis of Photo-Alignment Monomer 15

The weight of 14.6 g (100 mmol) of 4-acetylstyrene and 10.6 g (100 mmol)of benzaldehyde were added to 100 mL of dimethylformamide in a 300-mLflask and stirred to add 12.4 g (110 mmol) of potassium-tert-butoxide.The solution was reacted at approximately 110° C. for approximately 4hours and cooled, and thereafter 100 mL of water and 20.0 g of aceticacid were sequentially added and further ice-cooled to filter aprecipitated crystal. The obtained crystal was recrystallized bymethanol to thereby obtain a photo-alignment monomer 15.

[Synthesis Example 16] Synthesis of Photo-Alignment Monomer 16

A photo-alignment monomer 16 was obtained by replacing trans-4-methylhydroxycinnamate in Synthesis Example 3 with the equal mol amount of7-hydroxycoumarin, and by condensing in the same manner as in SynthesisExample 3.

[Reference Synthesis Example 1] Synthesis of Reference Photo-AlignmentMonomer 2

A styrene derivative 7 was obtained by replacing 4-vinyl benzoate inSynthesis Example 3 with the equal mol amount of the thermalcross-linkable monomer 1, replacing trans-4-methyl hydroxycinnamate inSynthesis Example 3 with the equal mol amount of suberic acid, and bycondensing in the same manner as in Synthesis Example 3.

Subsequently, a reference photo-alignment monomer 2 was obtained byreplacing 4-vinyl benzoate in Synthesis Example 3 with the equal molamount of the styrene derivative 7, and by condensing in the same manneras in Synthesis Example 3.

[Reference Synthesis Example 2] Synthesis of Reference Photo-AlignmentMonomer 3

A styrene derivative 8 was obtained by replacing trans-4-methylhydroxycinnamate in Synthesis Example 3 with the equal mol amount of 1,6-hexandiol, and by condensing in the same manner as in SynthesisExample 3.

Subsequently, a reference photo-alignment monomer 3 was obtained byreplacing 4-vinyl benzoate in Synthesis Example 3 with the equal molamount of the styrene derivative 8, replacing trans-4-methylhydroxycinnamate in Synthesis Example 3 with the equal mol amount oftrans-cinnamic acid, and by condensing in the same manner as inSynthesis Example 3.

The constitution of each monomer is shown in the following Tables 1 to3.

A chemical constitution of each synthesized monomer was confirmed by ¹HNMR measurement with the use of JEOL JNM-LA400WB manufactured by JEOLLtd.

TABLE 1 Thermal cross-linking monomer diethylene hydroxy glycol ethylhydroxy mono hydroxy 2-hydroxy meth- ethyl meth- ethyl ethyl 4-vynilacrylate acrylate acrylate acrylamide maleimide benzoate 1 2

TABLE 2 Self-cross-linkable thermal cross-linkinkable monomer 4-hydroxybutyl acrylate N-methoxy N-butoxy glycidyl glycidyl methyl methylmethacrylate ether acrylamide acrylamide 3 4

Photo-alignmnet monomer

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

Reference 1

Reference 2

Reference 3

[Production Example 1] Synthesis of Copolymer 1

The weight of 1.30 g of hydroxyethyl methacrylate and 3.95 g of thephoto-alignment monomer 4, and 50 mg of α,α′-azobisisobutyronitrile(AIBN) as a polymerization catalyst were dissolved in 25 ml of dioxane,and reacted at 90° C. for 6 hours. After the finish of the reaction, thesolution was purified by a reprecipitation method to thereby obtain acopolymer 1. The number-average molecular weight of the obtainedcopolymer was 22600.

[Production Examples 2 to 36] Synthesis of Copolymers 2 to 36

Copolymers 2 to 36 were synthesized in the same manner as in ProductionExample 1 by using the thermal cross-linkable monomer shown in Table 1and the photo-alignment monomer shown in Table 3, and another monomer asrequired.

[Comparative Production Examples 1 to 3] Synthesis of ComparativeCopolymers 1 to 3

Comparative copolymers 1 to 3 were synthesized in the same manner as inProduction Example 1 by using the thermal cross-linkable monomer shownin Table 1 and the photo-alignment monomer shown in Table 3.Incidentally, the reference photo-alignment monomer 1 is4-(6-methacryloxyhexyl-1-oxy)methyl ester cinnamate.

[Production Examples 37 to 54] Synthesis of Copolymers 37 to 54

Copolymers 37 to 54 were synthesized in the same manner as in ProductionExample 1 by using the thermal cross-linkable monomer shown in Tables 1and 2, and the photo-alignment monomer shown in Table 3.

Each of the copolymers is shown in the following Tables 4 and 5.

The number-average molecular weight (hereinafter referred to as Mn) ofeach synthesized copolymers was calculated by gel permeationchromatography (GPC) with the use of HLC-8220 GPC manufactured by TosohCorporation while regarding polystyrene as a standard reference materialand NMP as an eluant.

TABLE 4 Thermal cross-linkable monomer Photo-alignment monomer Othermonomer Addition Addition Addition amount amount amount (g) (g) (g) MnProduction hydroxyethyl methacrylate 1.30 Photo-alignment monomer 4 3.9522600 Example 1 Production hydroxybutyl acrylate 1.44 Photo-alignmentmonomer 4 3.95 24300 Example 2 Production diethylene glycol 1.74Photo-alignment monomer 4 3.95 19800 Example 3 monomethachlolateProduction hydroxyethyl acrylamide 1.15 Photo-alignment monomer 4 3.9520500 Example 4 Production 2-hydroxyethyl maleimide 1.41 Photo-alignmentmonomer 4 3.95 23500 Example 5 Production 4-vinyl benzoate 1.48Photo-alignment monomer 4 3.95 10600 Example 6 Production Thermalcross-linkable monomer 1 1.2 Photo-alignment monomer 4 3.95 9800 Example7 Production Thermal cross-linkable monomer 2 1.64 Photo-alignmentmonomer 4 3.95 11000 Example 8 Production hydroxyethyl methacrylate 1.3Photo-alignment monomer 4 3.95 20100 Example 9 Production hydroxyethylmethacrylate 1.3 Photo-alignment monomer 4 3.95 19600 Example 10Production hydroxyethyl methacrylate 1.3 Photo-alignment monomer 4 3.9552000 Example 11 Production hydroxyethyl methacrylate 1.3Photo-alignment monomer 4 3.95 19900 Example 12 Production hydroxyethylmethacrylate 1.3 Photo-alignment monomer 4 3.95 21000 Example 13Production hydroxyethyl methacrylate 1.3 Photo-alignment monomer 1 1.8820600 Example 14 Production hydroxyethyl methacrylate 1.3Photo-alignment monomer 2 2.5 22300 Example 15 Production hydroxyethylmethacrylate 1.3 Photo-alignment monomer 3 3.08 21300 Example 16Production hydroxyethyl methacrylate 1.3 Photo-alignment monomer 5 3.818600 Example 17 Production hydroxyethyl methacrylate 1.3Photo-alignment monomer 6 4.72 19600 Example 18 Production hydroxyethylmethacrylate 1.3 Photo-alignment monomer 7 5 21900 Example 19 Productionhydroxyethyl methacrylate 1.3 Photo-alignment monomer 8 4.1 20000Example 20 Production hydroxyethyl methacrylate 1.3 Photo-alignmentmonomer 9 2.5 17900 Example 21 Production hydroxyethyl methacrylate 1.3Photo-alignment monomer 10 2.8 25300 Example 22 Production hydroxyethylmethacrylate 1.3 Photo-alignment monomer 11 3.22 21800 Example 23Production hydroxyethyl methacrylate 1.3 Photo-alignment monomer 12 2.9422600 Example 24 Production hydroxyethyl methacrylate 1.3Photo-alignment monomer 13 3.5 20900 Example 25 Production hydroxyethylmethacrylate 1.3 Photo-alignment monomer 14 2.64 21700 Example 26Production hydroxyethyl methacrylate 1.3 Photo-alignment monomer 15 2.3420900 Example 27 Production hydroxyethyl methacrylate 1.3Photo-alignment monomer 16 2.92 21700 Example 28 Production hydroxybutylacrylate 1.44 Photo-alignment monomer 9 2.5 18900 Example 29 Productiondiethylene glycol 1.74 Photo-alignment monomer 9 2.5 19800 Example 30monomethacrylate Production hydroxyethyl acrylamide 1.15 Photo-alignmentmonomer 9 2.5 23000 Example 31 Production 2-hydroxyethyl maleimide 1.41Photo-alignment monomer 9 2.5 20700 Example 32 Production 4-vinylbenzoate 1.48 Photo-alignment monomer 9 2.5 9800 Example 33 ProductionThermal cross-linkable monomer 1 1.2 Photo-alignment monomer 9 2.5 10600Example 34 Production Thermal cross-linkable monomer 2 1.64Photo-alignment monomer 9 2.5 methylmethacrylate 2 12100 Example 35Production hydroxyethyl methacrylate 1.30 Photo-alignment monomer 4 3.95styrene 2.08 29800 Example 36 Comparative hydroxyethyl methacrylate 1.3Reference 3.46 9200 Production Photo-alignment monomer 1 Example 1Comparative hydroxyethyl methacrylate 1.3 Reference 4.36 21500Production Photo-alignment monomer 2 Example 2 Comparative hydroxyethylmethacrylate 1.3 Reference 3.78 19800 Production Photo-alignment monomer3 Example 3

TABLE 5 Self-cross-likable thermal Thermal cross- Photo-alignmentcross-linkable monomer linkable monomer monomer Addition AdditionAddition amount amount amount Kind (g) Kind (g) Kind (g) Mn Productionglycidyl methacrylate 1.42 Photo-alignment monomer 3 3.08 22000 Example37 Production 4hydroxybutyl acrylate 2.00 Photo-alignment monomer 3 3.0819800 Example 38 glycidyl ether Production N-methoxymeethyl 1.15Photo-alignment monomer 3 3.08 21400 Example 39 acrylamide ProductionN-butoxymethyl 1.57 Photo-alignment monomer 3 3.08 16700 Example 40acrylamide Production Thermal cross-linkable 3.68 Photo-alignmentmonomer 3 3.08 7200 Example 41 monomer 3 Production Thermalcross-linkable 4.28 Photo-alignment monomer 3 3.08 5100 Example 42monomer 4 Production glycidyl methacrylate 1.42 Photo-alignment monomer9 2.5 19700 Example 43 Production N-methoxymeethyl 1.15 Photo-alignmentmonomer 9 2.5 20600 Example 44 acrylamide Production Thermalcross-linkable 3.68 Photo-alignment monomer 9 2.5 6800 Example 45monomer 3 Production glycidyl methacrylate 1.42 Photo-alignment monomer11 3.22 17900 Example 46 Production N-methoxymeethyl 1.15Photo-alignment monomer 11 3.22 19500 Example 47 acrylamide ProductionThermal cross-linkable 3.68 Photo-alignment monomer 11 3.22 19900Example 48 monomer 3 Production glycidyl methacrylate 1.42 hydroxyethyl1.30 Photo-alignment monomer3 3.08 20100 Example 49 methacrylateProduction 4hydroxybutyl acrylate 2.00 Thermal cross-linkable 1.64Photo-alignment monomer 9 2.5 10600 Example 50 glycidyl ether monomer 2Production N-methoxymeethyl 1.15 hydroxyethyl 1.30 Photo-alignmentmonomer 11 3.22 18900 Example 51 acrylamide methacrylate ProductionN-butoxymethyl 1.57 Thermal cross-linkable 1.64 Photo-alignment monomer33.08 9800 Example 52 acrylamide monomer 2 Production Thermalcross-linkable 3.68 hydroxyethyl 1.30 Photo-alignment monomer 9 2.517800 Example 53 monomer 3 methacrylate Production Thermalcross-linkable 4.28 Thermal cross-linkable 1.64 Photo-alignment monomer11 3.22 11200 Example 54 monomer 4 monomer 2

Example 1 Preparation of Thermosetting Composition 1

A thermosetting composition 1 with the composition described below wasprepared.

-   -   Copolymer 1: 0.1 g    -   hexamethoxymethylmelamine (HMM): 0.01 g    -   para-toluenesulfonic acid monohydrate (PTSA): 0.0015 g    -   propylene glycol monomethyl ether (PGME): 2.1 g

(Formation of Alignment Layer)

The thermosetting composition prepared in Example 1 was applied to oneplane of a transparent glass substrate by spin coat, and heated anddried in an oven of 100° C. for 1 minute to form a cured film and obtaina coating film. This cured film surface was irradiated with polarizedultraviolet rays including emission lines of 313 nm, at 10 mJ/cm² to 30mJ/cm² in a vertical direction to the substrate normal line, by using anHg—Xe lamp and a Glan Taylor prism to thereby form an alignment layer.

(Production of Retardation Plate)

A photo-polymerization initiator IRGACURE™ 184 manufactured by BASF wasadded by 5% by mass to a solution in which the liquid crystallinemonomer represented by the following formula was dissolved incyclohexanone so as to be a solid content of 15% by mass to prepare apolymerizable liquid crystal composition.

The polymerizable liquid crystal composition was applied by spin coat toa plane, on which the alignment layer of the transparent glass substratewas formed, and heated in an oven of 70° C. for 1 minute to form acoating film. In this substrate, the polymerizable liquid crystalcomposition applied surface was irradiated with 300 mJ/cm² ofunpolarized ultraviolet rays including emission lines of 365 nm, under anitrogen atmosphere, by using an Hg—Xe lamp, to produce a retardationplate.

Examples 2 to 38 and Comparative Examples 1 to 3

A thermosetting composition of Examples 2 to 38 and Comparative Examples1 to 3 was prepared in the same manner as in Example 1 by usinghexamethoxymethylmelamine (HMM) or1,3,4,6-tetrakis(methoxymethyl)glycoluril (TMGU) as the cross-linkingagent, para-toluenesulfonic acid monohydrate (PTSA) orpara-toluenesulfonic acid pyridinium salt (PPTS) as the acid or the acidgenerator, and propylene glycol monomethyl ether (PGME) or methyl ethylketone (MEK) as the solvent to form an alignment layer and produce aretardation plate.

The composition of each thermosetting composition is shown in thefollowing Table 6.

Example 39 Preparation of Thermosetting Composition 39

A thermosetting composition 39 with the composition described below wasprepared.

-   -   Copolymer 1: 0.1 g    -   para-toluenesulfonic acid monohydrate (PTSA): 0.0015 g    -   propylene glycol monomethyl ether (PGME): 2.1 g

(Formation of Alignment Layer)

An alignment layer was formed in the same manner as in Example 1.

(Production of Retardation Plate)

A retardation plate was produced in the same manner as in Example 1.

Examples 40 to 66

A thermosetting composition of Examples 40 to 66 was prepared in thesame manner as in Example 39 by using para-toluenesulfonic acidmonohydrate (PTSA) or para-toluenesulfonic acid pyridinium salt (PPTS)as the acid or the acid generator, propylene glycol monomethyl ether(PGME) as the solvent, and hexamethoxymethylmelamine (HMM) or1,3,4,6-tetrakis(methoxymethyl)glycoluril (TMGU) as the cross-linkingagent to form an alignment layer and produce a retardation plate.

The composition of each thermosetting composition is shown in thefollowing Table 7.

[Evaluations]

The following evaluations were conducted for each obtained thermosettingcomposition and retardation plate.

(Sensitivity and Liquid Crystal Alignment Ability)

With regard to Examples 1 to 38 and Comparative Examples 1 to 3, twosheets of linear polarizing plates were made into a crossed Nicol stateto hold a retardation plate therebetween, which was visually observed.On the occasion of rotating the substrate, the evaluation was conductedwhile regarding the case in which a light and dark pattern observed inthe plane is clear as “◯”, the case that a light and dark patternobserved in the plane is clear but the alignment property is weak as“Δ”, and the case in which alignment defect is observed as “×”. Here,the alignment property being weak signifies the case of partially greyand non-uniform.

(Adhesion Properties)

With regard to Examples 1 to 38 and Comparative Examples 1 to 3, a notchwas made at an interval of 1 mm in a retardation plate with a bladecutter by using an equidistant spacer to form a grid pattern of 10×10.Subsequently, a cellophane adhesive tape was placed on the grid patternand tightly stuck to thereafter peel off the cellophane adhesive tape.The cut portion of the coating film after peeling off the cellophaneadhesive tape was observed. The case that the number of squares of thegrids, in which the coating film was peeled along the line of the cut orat the crosspoint, was less than 15% with respect to the number of allsquares of the grid pattern, was regarded as “A”, and the case that thenumber of squares of the grids was 15% or more was regarded as “B”.

TABLE 6 Evaluation Cross-linking Sensitivity and Copolymer agent AcidSolvent liquid crystal part by part by part by part by alignmentproperty Adhesion mass mass mass mass 10 mJ/cm² 20 mJ/cm² 30 mJ/cm²properties Example 1 Copolymer 1 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯◯ A Example 2 Copolymer 2 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ AExample 3 Copolymer 3 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example4 Copolymer 3 0.1 HMM 0.03 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 5Copolymer 3 0.1 HMM 0.05 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 6Copolymer 4 0.1 TMGU 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 7Copolymer 5 0.1 TMGU 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 8Copolymer 6 0.1 TMGU 0.01 PTSA 0.0015 PGME 2.1 ◯ ◯ ◯ A Example 9Copolymer 7 0.1 TMGU 0.01 PTSA 0.0015 PGME 2.1 ◯ ◯ ◯ A Example 10Copolymer 8 0.1 TMGU 0.01 PTSA 0.0015 PGME 2.1 ◯ ◯ ◯ A Example 11Copolymer 9 0.1 TMGU 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 12Copolymer 10 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 13Copolymer 11 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 14Copolymer 12 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 15Copolymer 13 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 16Copolymer 14 0.1 HMM 0.01 PPTS 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 17Copolymer 15 0.1 HMM 0.01 PPTS 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 18Copolymer 16 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 19Copolymer 17 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 20Copolymer 18 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 21Copolymer 19 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 22Copolymer 20 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 23Copolymer 21 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 24Copolymer 22 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 25Copolymer 23 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 26Copolymer 24 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 27Copolymer 25 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 28Copolymer 26 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 29Copolymer 27 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 30Copolymer 28 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 Δ ◯ ◯ A Example 31Copolymer 29 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 32Copolymer 30 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 33Copolymer 31 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 34Copolymer 32 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A Example 35Copolymer 33 0.1 HMM 0.01 PTSA 0.0015 PGME 2.1 ◯ ◯ ◯ A Example 36Copolymer 34 0.1 HMM 0.03 PTSA 0.0015 PGME 2.1 ◯ ◯ ◯ A Example 37Copolymer 35 0.1 HMM 0.01 PTSA 0.0015 PGME 2.1 ◯ ◯ ◯ A Example 38Copolymer 36 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 ◯ ◯ ◯ A ComparativeComparative 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 X X ◯ B Example 1Copolymer 1 Comparative Comparative 0.1 HMM 0.01 PTSA 0.0015 PGMEA 2.1 XX Δ B Example 2 Copolymer 2 Comparative Comparative 0.1 HMM 0.01 PTSA0.0015 PGMEA 2.1 X X Δ B Example 3 Copolymer 3

The thermosetting composition of Examples 1 to 38 offered favorableliquid crystal alignment ability at small light exposure and highsensitivity.

Also, any of the cases of forming an alignment layer by using thethermosetting composition of Examples 1 to 38 offered not only favorableliquid crystal alignment ability but also favorable adhesion properties.The reason therefor is conceived to be that both the photo-alignmentconstitutional unit and the thermal cross-linking constitutional unit ofthe copolymer include a styrene skeleton so that an interaction of then-electron system acts with liquid crystal molecules.

(Liquid Crystal Alignment Property)

With regard to Examples 39 to 66, two sheets of linear polarizing plateswere made into a crossed Nicol state to hold a retardation platetherebetween, which was visually observed. On the occasion of rotatingthe substrate, the evaluation was conducted while regarding the casethat a light and dark pattern observed in the plane is greatly clear as“⊙”, the case that a light and dark pattern observed in the plane isclear as “◯”, and the case that alignment defect is observed as “×”.

TABLE 7 Evaluation Cross- result linking Liquid Copolymer Acid Solventagent crystal part by part by part by part by alignment Kind mass Kindmass Kind mass Kind mass property Example 39 Copolymer 37 0.1 PTSA0.0015 PGME 2.1 ⊚ Example 40 Copolymer 38 0.1 PPTS 0.0015 PGME 2.1 ⊚Example 41 Copolymer 39 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 42 Copolymer40 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 43 Copolymer 41 0.1 PTSA 0.0015PGME 2.1 ⊚ Example 44 Copolymer 42 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 45Copolymer 43 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 46 Copolymer 44 0.1 PTSA0.0015 PGME 2.1 ⊚ Example 47 Copolymer 45 0.1 PTSA 0.0015 PGME 2.1 ⊚Example 48 Copolymer 46 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 49 Copolymer47 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 50 Copolymer 48 0.1 PTSA 0.0015PGME 2.1 ⊚ Example 51 Copolymer 49 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 52Copolymer 50 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 53 Copolymer 51 0.1 PTSA0.0015 PGME 2.1 ⊚ Example 54 Copolymer 52 0.1 PTSA 0.0015 PGME 2.1 ⊚Example 55 Copolymer 53 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 56 Copolymer54 0.1 PTSA 0.0015 PGME 2.1 ⊚ Example 57 Copolymer 41 0.1 PTSA 0.0015PGME 2.1 HMM 0.01 ◯ Example 58 Copolymer 42 0.1 PTSA 0.0015 PGME 2.1TMGU 0.01 ◯ Example 59 Copolymer 45 0.1 PPTS 0.0015 PGME 2.1 HMM 0.01 ◯Example 60 Copolymer 48 0.1 PTSA 0.0015 PGME 2.1 HMM 0.01 ◯ Example 61Copolymer 49 0.1 PTSA 0.0015 PGME 2.1 HMM 0.01 ◯ Example 62 Copolymer 500.1 PTSA 0.0015 PGME 2.1 HMM 0.01 ◯ Example 63 Copolymer 51 0.1 PTSA0.0015 PGME 2.1 HMM 0.01 ◯ Example 64 Copolymer 52 0.1 PTSA 0.0015 PGME2.1 HMM 0.01 ◯ Example 65 Copolymer 53 0.1 PTSA 0.0015 PGME 2.1 HMM 0.01◯ Example 66 Copolymer 54 0.1 PTSA 0.0015 PGME 2.1 HMM 0.01 ◯

The invention claimed is:
 1. A thermosetting composition with aphoto-alignment property, comprising a copolymer containing aphoto-alignment constitutional unit represented by the following formula(1) and a thermal cross-linking constitutional unit:

in the formula (1), X represents a photo-alignment group causing aphoto-isomerization reaction or a photo-dimerization reaction, L¹represents a single bond, —O—, —S—, —COO—, —COS—, —CO—, —OCO—,—OCO(CH₂)_(n)COO—, —OCOCH₂CH₂OCH₂CH₂COO—, —OCOC₆H₄O—, —OCOC₆H₁₀O—,—COO(CH₂)_(n)O—, —COOC₆H₄O—, —COOC₆H₁₀O—, —OC₆H₄O—, —OC₆H₁₀O—, or—(CH₂)_(n)O—, n represents 1 to 4, R¹ represents a hydrogen atom or amonovalent organic group, and k represents 1 to
 5. 2. The thermosettingcomposition with a photo-alignment property according to claim 1,further comprising a cross-linking agent for bonding to a thermalcross-linking group of the thermal cross-linking constitutional unit. 3.The thermosetting composition with a photo-alignment property accordingto claim 2, wherein the photo-alignment group is a cinnamoyl group, achalcone group, a coumarin group, an anthracene group, a quinolinegroup, an azobenzene group, or a stilbene group.
 4. The thermosettingcomposition with a photo-alignment property according to claim 1,wherein the thermal cross-linking constitutional unit comprises aself-cross-linkable cross-linking group.
 5. The thermosettingcomposition with a photo-alignment property according to claim 1,wherein the photo-alignment group is a cinnamoyl group.
 6. Thethermosetting composition with a photo-alignment property according toclaim 1, wherein the thermal cross-linking group of the thermalcross-linking constitutional unit is a hydroxy group.
 7. An alignmentlayer comprising a copolymer including a photo-alignment constitutionalunit represented by the following formula (1) and a cross-linkingstructure, and the alignment layer comprising a photo-dimerizationstructure or a photo-isomerization structure of a photo-alignment groupin the photo-alignment constitutional unit:

in the formula (1), X represents a photo-alignment group causing aphoto-isomerization reaction or a photo-dimerization reaction, L¹represents a single bond, —O—, —S—, —COO—, —COS—, —CO—, —OCO—,—OCO(CH₂)_(n)COO—, —OCOCH₂CH₂OCH₂CH₂COO—, —OCOC₆H₄O—, —OCOC₆H₁₀O—,—COO(CH₂)_(n)O—, —COOC₆H₄O—, —COOC₆H₁₀O—, —OC₆H₄O—, —OC₆H₁₀O—, or—(CH₂)_(n)O—, n represents 1 to 4, R¹ represents a hydrogen atom or amonovalent organic group, and k represents 1 to
 5. 8. The alignmentlayer according to claim 7, wherein the cross-linking structure is across-linking structure obtained by bonding a thermal cross-linkinggroup of the thermal cross-linking constitutional unit to across-linking agent.
 9. The alignment layer according to claim 8,wherein the photo-alignment group is a cinnamoyl group, a chalconegroup, a coumarin group, an anthracene group, a quinoline group, anazobenzene group, or a stilbene group.
 10. The alignment layer accordingto claim 7, wherein the cross-linking structure is a cross-linkingstructure of a self-cross-linkable cross-linking group in the thermalcross-linking constitutional unit.
 11. A substrate with an alignmentlayer comprising a substrate, and the alignment layer disposed on thesubstrate and formed from the thermosetting composition with aphoto-alignment property according to claim
 1. 12. A substrate with analignment layer comprising a substrate, and the alignment layeraccording to claim 7, disposed on the substrate.
 13. A retardation platecomprising a substrate, the alignment layer according to claim 7,disposed on the substrate, and a retardation layer disposed on thealignment layer.
 14. A device comprising the alignment layer accordingto claim 7.